Workload and Leadership in Non-Profit Organizations: An Empirical Study for Balancing Project Workload and Achieving Project Success ()
1. Introduction
Non-profit organizations (NPOs) have become central actors in modern societies, operating across sectors such as humanitarian aid, health, education, environmental protection, and community development. Together, they form what scholars describe as the “third sector”, distinct from both the state and the market, yet increasingly influenced by the dynamics of both (Weisbrod, 1997). Over recent decades, the sector has expanded significantly. In the United States alone, nonprofit employment grew by 18.6% between 2007 and 2017, far exceeding the 6.2% growth of the private for-profit sector (Friesenhahn, 2025). Globally, NPOs contribute substantially to the achievement of the Sustainable Development Goals (SDGs), channeling billions of dollars annually toward social missions.
Despite this growth, organizational capacity has not advanced at the same pace. The sector faces a structural paradox: increasing societal demand for services alongside worsening workforce and resource constraints. Surveys indicate severe staffing challenges, with turnover rates in nonprofits reaching approximately 19%, compared to 12% in comparable sectors (Friesenhahn, 2025). Recent research has found that 95% of nonprofit leaders are concerned about staff burnout, while nearly half struggle to fill vacancies. Similarly in the US, the National Council of nonprofits reported in 2023 that almost 75% of organizations face persistent staffing shortages, particularly in programme delivery roles.
This environment of chronic pressure directly affects project implementation. NPOs increasingly rely on projects as the primary mechanism for delivering social missions, requiring coordination, leadership, and sustained team engagement. However, high turnover, understaffing, and limited resources undermine the conditions necessary for project success. Consequently, understanding how leadership competences can mitigate these challenges has become both an academic and operational priority.
Although project-based work has become central to nonprofit operations, project success rates remain low. Research consistently attributes this underperformance to governance limitations, resource scarcity, and inadequate project management competences (Nencini, Romaioli, & Meneghini, 2016; Saidoun, Bodea, & Radujković, 2023). Across industries generally, only 35% of projects worldwide achieve their objectives fully. In the nonprofit context, project failure carries particularly serious consequences, including unmet community needs, reduced donor confidence, and weakened social impact.
Studies on project management competences increasingly emphasize the importance of relational and interpersonal leadership factors such as communication, emotional intelligence, and leader-follower exchange relationships (Ochoa Pacheco, Coello-Montecel, Tello, Lasio, & Armijos, 2023). However, most of this research has been conducted in private and public sector settings. The nonprofit sector, characterized by mission-driven cultures, volunteer-professional dynamics, and resource limitations, remains comparatively understudied.
Addressing this gap, Saidoun et al. (2023) conducted an international mixed-methods study involving 205 nonprofit stakeholders across 33 countries. Their findings identified Leader-Leader Exchange (LLX), Shared Values (SV), result orientation, and personal communication as key determinants of project success in NPOs. Yet an important and unexpected theme emerged during the qualitative phase of the study: workload. Participants repeatedly highlighted excessive workload, limited resources, and pressure to deliver results as major contributors to stress, reduced motivation, delays, and project failure. These findings align with broader sector-wide evidence linking overload to burnout and staff turnover. Despite its significance, workload balance has not yet been fully integrated into nonprofit project success models.
This article addresses that gap by proposing an empirical study in which workload balance becomes an explicit variable influencing project success. The study argues that LLX and Shared Values function as leadership mechanisms capable of buffering the negative effects of high workload. Specifically, when project sponsors maintain high-quality relationships with project managers—characterized by trust, communication, and strategic alignment—and when project teams share strong organizational values, these conditions can reduce the harmful effects of workload pressure on project performance.
The study builds on the validated model developed by (Saidoun et al., 2023) and extends it in three important ways. First, it introduces workload balance as a central theoretical construct rather than treating it merely as contextual background. Second, it proposes a more homogeneous sampling strategy focused either on volunteer-based or paid-staff NPOs to overcome interpretive limitations caused by organizational heterogeneity in prior research. Third, it connects nonprofit project management research with emerging discussions on ESG governance and workforce sustainability (Im, Grundhoefer, & Smith Arrillaga, 2024; Mariani, Caccialanza, Bugarčić, Slavkovic, & Mancini, 2025). In doing so, the article responds to calls for greater attention to mediating and moderating variables in the relationship between leadership competences and project outcomes (Martens, Machado, Martens, & de Freitas, 2018; Martens & Carvalho, 2016).
The theoretical foundation of this article combines Social Exchange Theory (SET) and Leadership Theory. SET, originating from later developed by Cropanzano and Mitchell (2005), explains how individuals maintain commitment and performance when they perceive organizational relationships as supportive, fair, and reciprocal. In resource-constrained nonprofit environments, where financial incentives are often limited, the quality of interpersonal exchange relationships becomes especially important for sustaining motivation and engagement.
The second theoretical pillar is the Leader-Member Exchange (LMX) tradition, adapted here into the concept of Leader-Leader Exchange (LLX). LLX focuses specifically on the relationship between project managers and organizational sponsors or senior leaders. While much leadership research emphasizes downward relationships between leaders and teams, prior findings suggest that upward and lateral leadership exchanges also significantly affect project performance (Saidoun et al., 2023). Integrating SET and LLX within a nonprofit-specific empirical study therefore provides a coherent explanation of how leadership competences can mediate the relationship between workload balance and project success.
The remainder of this article is organized as follows. Section 2 reviews the literature on nonprofit project management, Social Exchange Theory, LLX, and workload in project environments. Section 3 develops the empirical study and presents the research hypotheses. Section 4 outlines the proposed methodology, including sampling strategy, measurement instruments adapted from Saidoun et al. (2023), and analytical techniques. Section 5 discusses expected contributions, practical implications, and limitations. Finally, Section 6 concludes by summarizing the study and proposing directions for future research.
2. Literature Review
First The non-profit sector has become an increasingly important component of modern economies and societies. Operating between the state, market, and civil society, non-profit organizations (NPOs) rely heavily on project-based work to deliver services and fulfil social missions (Weisbrod, 1997). Over recent decades, the sector has experienced substantial growth alongside intensified professionalization, accountability requirements, and competition for funding (Friesenhahn, 2025). As a result, project management competences have become essential for organizational effectiveness and survival. Despite this shift, project success rates within NPOs remain comparatively low. Research consistently identifies governance limitations, resource scarcity, and insufficient project management competences as key contributors to underperformance (Nencini et al., 2016; Saidoun et al., 2023). Workforce pressures further intensify these challenges. Reports indicate widespread staff burnout and chronic vacancies across the sector, particularly in programme delivery roles critical to project execution (Boesso & Cerbioni, 2024; Johnson, 2009). High turnover, understaffing, and mission-driven overcommitment create a distinctive organizational environment in which workload management becomes central to project success.
Workload refers to the quantity, complexity, and intensity of tasks, responsibilities, and activities assigned to an employee within a given period. Workload pressure, often termed workload overload, occurs when job demands exceed an individual’s available resources, capabilities, or time, leading to strain, fatigue, and reduced performance. While workload itself is a neutral construct that can vary across roles and contexts, workload overload represents a condition of imbalance between demands and capacity. In contrast, workload balance describes the optimal alignment between work demands and the employee’s resources, skills, and available time. The workload balance serves as a key indicator of organizational effectiveness, whereas workload overload is commonly associated with negative outcomes such as burnout, decreased job satisfaction, and impaired performance. So the construct per se refers primarily to a sustainability construct. This literature review examines the intersection of workload, leadership competences, and project outcomes in NPOs. It focuses particularly on the roles of Leader-Leader Exchange (LLX) and Shared Values (SV) as mechanisms capable of mitigating the negative effects of excessive workload on project performance. Social Exchange Theory (SET) provides the primary theoretical foundation for understanding these relationships. Originating from Blau’s exchange framework and further developed by (Cropanzano & Mitchell, 2005) and (Mitchell & Clark, 2021) SET argues that workplace relationships are governed by reciprocal exchanges. Employees who perceive fairness, support, and recognition from leaders and organizations are more likely to reciprocate with commitment and discretionary effort. Conversely, when demands exceed available resources, exchange relationships deteriorate, leading to disengagement, burnout, and turnover. Recent scholarship has criticized simplistic interpretations of SET that reduce workplace relationships to purely transactional exchanges (Madison, Eva, De Cieri, & Goh, 2024). In practice, reciprocity is shaped by organizational context, timing, and social norms. This is particularly relevant in NPOs, where resource scarcity amplifies the importance of intangible exchanges such as emotional support, fair workload distribution, recognition, and shared purpose. Because financial rewards are often limited, leadership quality becomes one of the primary mechanisms sustaining employee engagement and commitment. Within this framework, workload itself can be studied empirically. Leaders who allocate tasks fairly and communicate transparently help reduce emotional exhaustion and foster perceptions of organizational justice (Fehr, Yam, & Dang, 2015). In nonprofit settings, where employees and volunteers frequently operate under demanding conditions, equitable workload management becomes essential to maintaining both morale and project effectiveness. The concept of Leader-Leader Exchange (LLX) extends this discussion into project governance. Adapted from Leader-Member Exchange (LMX) theory (Graen & Uhl-Bien, 1995), LLX focuses on the relationship between project managers and senior organizational leaders such as executive directors, sponsors, or board members. Unlike traditional leadership studies emphasizing downward leader-to-team relationships, LLX examines upward and lateral exchanges within the organizational hierarchy. This dimension is especially important in NPOs, where project managers often have limited formal authority and must operate within constrained resource environments. High-quality LLX relationships provide project managers with strategic support, communication access, decision-making flexibility, and conflict resolution pathways that can directly influence project implementation. Empirical evidence supports the importance of these relationships. Research shows that high-quality exchange relationships improve project outcomes and can mediate the effects of transformational leadership on project success. (Saidoun et al., 2023) found that LLX positively affects project performance in NPOs, although its impact is partly mediated by team-level result orientation. These findings suggest that project success depends not only on technical competences but also on the quality of organizational relationships surrounding project managers. Importantly, the role of LLX in managing workload has received little attention. In project environments characterized by excessive demands and limited resources, sponsor involvement becomes crucial in shaping how workloads are distributed, escalated, and resolved. Lack of sponsor support may intensify project pressure, while effective LLX relationships can help redistribute resources and reduce overload. Shared values constitute another critical factor in nonprofit project environments. Shared values refer to the extent to which organizational members hold common ethical commitments, mission orientations, and strategic priorities. In NPOs, these values serve both motivational and coordinative functions. Mission alignment encourages commitment and persistence under difficult conditions, while value alignment facilitates trust, cooperation, and flexible responses to resource constraints (Saidoun et al., 2023). Research increasingly links value alignment with employee retention, leadership effectiveness, and workload resilience. When organizational values and leadership culture are misaligned, frustration and stress contribute directly to burnout and resignation. Conversely, teams united by strong shared values are more likely to perceive workload as a collective responsibility rather than an individual burden (Shah & Kundi, 2023). This distinction is especially significant in nonprofits, where employees and volunteers often accept demanding workloads because of their commitment to a broader social mission (Robichau, Sandberg, & Russo, 2024). However, this motivational dynamic has limits. When staff perceive workload expectations as exploitative or unsupported by leadership, the psychological contract underlying mission commitment can quickly deteriorate. Excessive workload combined with inadequate recognition or support weakens the protective effect of shared values, increasing burnout and turnover risks (Smallman & Parry, 2025). Although workload is widely recognized as a practical challenge within NPOs, it remains underdeveloped as a theoretical construct in project management research. Existing studies typically treat workload as a contextual condition rather than an independent variable influencing project outcomes. This review argues that workload should instead be conceptualized as a central factor affecting project performance and team sustainability. Qualitative evidence from Saidoun et al. (2023) highlights this issue clearly. Interviews with nonprofit project managers revealed that excessive workloads, insufficient staffing, and pressure for continuous result delivery frequently generated stress, delays, and project dysfunction. Participants emphasized that strong result orientation, while generally positive, could become counterproductive when combined with chronic resource shortages. These findings align with broader workforce research in the nonprofit sector. NPOs often face structural tensions between mission demands and organizational capacity (Taylor, Cornelius, & Colvin, 2014). Staff members are commonly required to manage multiple roles simultaneously, while project timelines are shaped by donor expectations rather than realistic workload capacity. This dynamic creates a cycle in which overwork leads to burnout, burnout contributes to turnover, and turnover further intensifies workload for remaining staff. From a project management perspective, excessive workload directly undermines project success. Cognitive overload reduces the ability of team members to maintain quality, communicate effectively, solve problems adaptively, and sustain long-term engagement. The critical issue therefore becomes whether leadership structures exist to buffer the negative effects of workload pressure. Building on these insights, this article proposes an empirical study in which LLX and shared values jointly moderate the relationship between workload and project success. The study extends the validated model developed by Saidoun et al. (2023) by placing workload at the center of analysis. First, high-quality LLX relationships provide project managers with access to organizational resources, strategic support, and governance flexibility. Frequent communication, active sponsor involvement, and strategic alignment allow project managers to redistribute tasks more equitably and address workload imbalances before they become critical. This interpretation aligns with fairness-based perspectives on leadership and resource allocation (Fehr et al., 2015). Second, shared values create a team environment characterized by trust, collective responsibility, and mutual support. Teams strongly committed to the organization’s mission are more likely to collaborate effectively, support overwhelmed colleagues, and proactively communicate emerging workload pressures. Shared values therefore contribute to organizational resilience by fostering adaptive cooperation under resource constraints. Third, the interaction between LLX and shared values creates a compounding buffering effect. When project managers experience strong support from senior leadership while simultaneously leading cohesive, mission-aligned teams, organizations are better positioned to absorb workload pressures without compromising project performance. This integrated perspective aligns with emerging ESG-oriented approaches to project management that emphasize employee well-being, equitable governance, and sustainable leadership practices as essential components of organizational performance (Mariani et al., 2025). The literature review reveals a significant gap at the intersection of nonprofit project management, workload research, and leadership exchange theory. Although each field has developed independently, their integration remains limited. Existing studies rarely conceptualize workload as a central explanatory variable, and few examine how leadership relationships shape workload outcomes in project-based nonprofit environments. This study addresses these limitations by introducing workload balance explicitly into the nonprofit project success model and by theorizing LLX and shared values as joint mechanisms capable of mediating workload pressures. In doing so, the study contributes to broader calls within project management scholarship for greater attention to mediating and moderating variables influencing project success (Martens et al., 2018). It also strengthens recognition of the nonprofit sector as a distinctive organizational context requiring specialized leadership and project management frameworks.
3. Empirical Study and Research Analysis
This section develops the empirical study construct that constitutes the theoretical core of the article. Drawing on the validated research model of (Saidoun et al., 2023), Social Exchange Theory (SET), and the emergent literature on workload in project-based non-profit organizations, the study introduces workload balance as a new focal variable and articulates the mechanisms through which Leader-Leader Exchange (LLX) and Shared Values (SV) jointly influence both workload outcomes and project success. Figure 1 presents the extended research model, followed by a structured derivation of each hypothesis.
Figure 1. Extended research model: LLX, Shared Values, Workload Balance, and Project Success in NPOs. Source: Extended from Saidoun et al. (2023), adapted from (Chen & Lin, 2018).
3.1. Overview of the Extended Research Model
The original research model validated in (Saidoun et al., 2023) established a system of relationships among four project management competence elements—LLX, SV, Result Orientation (RO), and Personal Communication (PC)—and their collective influence on Project Success (PS) in NPOs. The model confirmed, inter alia, that: LLX has a significant direct positive effect on PS (H1); SV has a significant positive direct effect on PS (H2); RO of the project team positively mediates the relationship between LLX and PS (H3a) and between SV and PS (H3b); and PC positively moderates the relationship between LLX and PS (H4a) and between SV and PS (H4b). The extended model proposed in this article preserves this validated architecture and introduces a new variable: Workload Balance (WB), defined as the perceived equitability and sustainability of task distribution within and around the project team. Workload Balance is positioned as: 1) an outcome variable influenced jointly by LLX and SV; 2) a mediating variable between LLX/SV and Project Success; and 3) an explanatory variable for a subset of the mechanisms through which excessive Result Orientation negatively affects project outcomes—a nuanced finding from Saidoun et al. (2023) that prior literature had not theorized. Personal Communication (PC) is retained as a moderator across key pathways in the extended model. The framework is grounded in two complementary theoretical logics. From a Social Exchange Theory perspective, Workload Balance is conceptualized as a resource whose equitable distribution is governed by the quality and reciprocity of leadership exchange relationships. When LLX is high—meaning the project manager enjoys active, trust-based engagement with project sponsors—the project manager gains access to organizational resources (authority, flexibility, conflict escalation) that enable more equitable task allocation. Similarly, when SV is strong, team members experience workload as a shared collective responsibility rather than an individual burden, activating mutual support mechanisms that buffer against overload. From a Leadership Theory perspective, both LLX and SV represent relational competences that shape the psychological climate within which work demands are interpreted and managed.
3.2. Derivation of Hypothesis
3.2.1. Direct Effects of LLX and Shared Values on Project Success (H1 and H2—Retained)
The direct relationships between LLX and project success, and between SV and project success, were empirically validated in (Saidoun et al., 2023) using a bootstrap-integrated structural equation model applied to 205 NPO professionals across 33 countries. Both relationships were confirmed at p < 0.001, establishing them as robust and replicable. The present framework retains these hypotheses as baseline relationships to be tested in the new, more homogeneous sample, thereby permitting a direct comparison with prior findings and assessing whether the strength of these effects varies across volunteer-only versus paid-staff NPO contexts.
H1: Leader-Leader Exchange (LLX) has a significant positive direct effect on Project Success (PS) in NPOs
H2: Shared Valued (SV) has a significant positive direct effect on Project Success in NPOs
3.2.2. Result Orientation as Mediator between LLX/SV and Project Success (H3a and H3b—Retained)
Saidoun et al. (2023) found that Result Orientation (RO) of the project team positively mediates both the LLX → PS relationship (indirect effect = 0.743, p < 0.001) and the SV → PS relationship (net indirect effect = +0.31, p < 0.001). These findings established RO as a critical transmission mechanism: the leadership quality at the top of the project hierarchy and the value alignment within the team do not translate directly into project success—they do so partly by energising and focussing the team’s goal-directed behaviour. Importantly, the same data revealed that an excessive degree of RO can have negative consequences—generating stress, narrowing focus away from stakeholder well-being, and paradoxically causing project delays. This nuance is central to the workload argument developed in H5 - H7 below. H3a and H3b are retained for replication and contextual comparison.
H3a: Result Orientation (RO) of the project team positively mediates the relationship between LLX and Project Success (PS) in NPOs
H3b: Result Orientation (RO) of the project team positively mediates the relationship between Shared Values (SV) and Project Success (PS) in NPOs
3.2.3. Personal Communication as Moderator of LLX/SV Pathways (H4a and H4b—Retained)
Personal Communication (PC) was confirmed as a significant positive moderator of the LLX → PS relationship (combined moderation effect = 0.33, p < 0.001) and of the SV → PS relationship (combined direct effects = 1.05 - 1.08, p < 0.001) in (Saidoun et al., 2023). These findings align with the established literature on the role of communication in leadership effectiveness and extend it to the NPO project context. In the extended study, PC is also studied to moderate the new pathways from LLX and SV to Workload Balance (H6a and H6b below), as the frequency and quality of communication between project sponsors and managers, and among team members, directly shapes how workload pressures are surfaced, negotiated, and redistributed.
H4a: Personal Communication (PC) positively moderates the relationship between LLX and Project Success (PS) in NPOs
H4b: Personal Communication (PC) positively moderates the relationship between Shared Values (CV) and Project Success (PS) in NPOs
3.2.4. New Hypotheses: LLX, Shared Values, and Workload Balance (H5a, H5b, H6a, H6b)
The new hypotheses introduced in this article concern the pathways linking LLX and SV to Workload Balance (WB). Workload Balance is defined here as the degree to which project team members perceive the distribution of tasks, responsibilities, and time demands across the project as equitable, sustainable, and responsive to individual capacity. This construct is conceptually grounded in the task fairness literature (Fehr et al., 2015) and operationally anchored in the NPO workforce context where chronic overload has been identified as a primary driver of burnout and project underperformance (Im et al., 2024).
H5a—LLX and Workload Balance: When a project manager enjoys a high-quality LLX relationship with their sponsor—characterized by trust, active involvement, and open communication—they gain decisional resources that enable a more equitable distribution of project tasks. The sponsor’s engagement provides a governance buffer: when workload becomes unsustainable, the project manager has a legitimate and responsive escalation pathway. This reasoning is grounded in SET, where high-quality exchange relationships are theorized to provide access to both tangible and intangible resources (Cropanzano & Mitchell, 2005). It also reflects the practical observation made by project managers in the ethnographic phase of (Saidoun et al., 2023), where sponsor presence and communication were described as directly moderating workload-related stress.
H5a: Leader-Leader Exchange (LLX) has a significant positive effect I World Load Balance (WB) in NPO projects.
H5b—Shared Values and Workload Balance: When project team members share strong organizational values—a commitment to the NPO’s mission, to mutual support, and to collective responsibility—workload is experienced as a shared challenge rather than an individual burden. Shared Values in teams are more likely to spontaneously redistribute tasks, cover for overloaded colleagues, and flag capacity concerns to project leadership before they become critical. This logic draws on the cohesion-building function of shared values (Gillespie & Mann, 2004) and on recent findings showing that value misalignment in NPOs is a primary driver of stress and attrition (Shah & Kundi, 2023).
H5b: Shared Values (SV) has a significant positive effect in Workload Balance (WB) in NPO projects.
H6a—PC as moderator of LLX → WB: The effect of LLX on Workload Balance is theorized to be amplified by the frequency and quality of Personal Communication between the project manager and the project sponsor. When LLX is high but communication is infrequent or impersonal, the relational capital of the exchange relationship may not translate into timely workload interventions. On the other end, when personal communication is frequent and trust-based, workload pressures are more likely to be surfaced early, discussed collaboratively, and resolved through sponsor-level resource adjustments. This parallels the moderation found by Saidoun et al. (2023) in the LLX → PS pathway, where PC strengthened the leadership-success link precisely by improving information flow and decisional clarity.
H6a: Personal Communication (PC) positively moderates the relationship between LLX and Workload Lod Balance (WB).
H6b—PC as moderator of SV → WB: Similarly, the effect of Shared Values on Workload Balance is theorized to depend on the quality of communication through which those values are enacted and reinforced. Values that are articulated but not practiced—not lived daily, in the terms of (Saidoun et al., 2023) ethnographic respondents—have limited capacity to generate the collective solidarity that buffers against workload overload. Personal Communication serves as the transmission medium through which shared values are operationalized: it enables the project leader to signal collective responsibility norms, to acknowledge individual capacity limits, and to mobilize the team’s mutual support culture when workload becomes acute.
H6b: Personal Communication (PC) positively moderates the relationship between Shared Values (SV) and Workload Balance (WB) in NPO projects
3.2.5. Workload Balance as a Mediator of Project Success (H7)
The final new hypothesis concerns the relationship between Workload Balance and Project Success. Drawing on the workload-performance literature and the NPO-specific evidence reviewed in Section 2, the argument is straightforward: when workload is perceived as equitable and sustainable, project team members retain the cognitive bandwidth, motivation, and relational capacity needed to execute project tasks effectively, manage stakeholder relationships, and maintain quality standards. Conversely, when workload is chronically excessive, the cascade of stress, absenteeism, reduced motivation, and turnover directly undermines project timelines, budget adherence, and deliverable quality—as documented in Saidoun et al. (2023) through the ethnographic findings, and corroborated by the broader nonprofit workforce literature. H7 thus positions Workload Balance as a mediating variable between the leadership competence inputs (LLX and SV) and the project success outcome—providing the mechanistic link that explains how relational leadership quality translates into tangible project performance improvements in the NPO context.
H7: Workload Balance (WB) positively mediates the relationship between the leadership competence inputs (LLX SV) and project Success in NPO projects
3.3. Summary of Hypothesis
Table 1 summarises all hypotheses included in the extended research model, distinguishing between retained hypotheses from the prior validated model and new hypotheses introduced by this study.
Table 1. Summary of research hypotheses in the extended model.
Hypothesis |
Relationship |
Type |
Status |
H1 |
LLX → Project Success (PS) |
Direct effect |
Retained from Saidoun et al. (2023) |
H2 |
SV → Project Success (PS) |
Direct effect |
Retained from Saidoun et al. (2023) |
H3a |
LLX → RO → PS (RO as mediator) |
Mediation |
Retained from Saidoun et al. (2023) |
H3b |
SV → RO → PS (RO as mediator) |
Mediation |
Retained from Saidoun et al. (2023) |
H4a |
PC moderates LLX → PS |
Moderation |
Retained from Saidoun et al. (2023) |
H4b |
PC moderates SV → PS |
Moderation |
Retained from Saidoun et al. (2023) |
H5a |
LLX → Workload Balance (WB) |
Direct effect |
NEW—this study |
H5b |
SV → Workload Balance (WB) |
Direct effect |
NEW—this study |
H6a |
PC moderates LLX → WB |
Moderation |
NEW—this study |
H6b |
PC moderates SV → WB |
Moderation |
NEW—this study |
H7 |
WB mediates LLX/SV → PS |
Mediation |
NEW—this study |
Source: Author, extended from Saidoun et al. (2023).
3.4. Theoretical Contribution to the Study
The extended study makes three distinct theoretical contributions to the NPO project management literature. First, it transforms workload from a contextual constraint—a background condition acknowledged in prior literature but not modelled—into a theoretically specified mediating variable with its own causal architecture. This move positions workload governance as a legitimate object of project management competence development, not merely an operational challenge to be managed ad hoc. Second, the study enriches the application of Social Exchange Theory in the project leadership context by conceptualizing the equitable distribution of workload as an intangible exchanged resource—comparable in its psychological significance, within the resource-scarce environment of NPOs, to the material rewards that motivate exchange behaviour in for-profit contexts. This enrichment responds directly to critiques of overly simplified applications of SET in leadership research (Madison et al., 2024) by specifying a concrete, contextually calibrated exchange mechanism. Third, by connecting the LLX-SV-PS architecture to the ESG governance discourse—specifically the social and governance dimensions of organizational sustainability in project-based organizations (Mariani et al., 2025)—the study situates NPO project management within a broader institutional conversation about responsible organizational practice. This connection is not merely rhetorical: it implies that improvements in workload governance through LLX and SV development constitute a measurable ESG contribution, with implications for how NPOs communicate their organizational practices to donors, funders, and regulatory bodies.
4. Research Methodology
This section presents the research methodology proposed to empirically test the empirical study structure developed in Section 3. The design builds directly on the validated methodology of (Saidoun et al., 2023), extending it in three directions: the introduction of a focused, homogeneous sampling strategy that addresses the heterogeneity limitation of the prior study; the addition of a new measurement scale for the Workload Balance (WB) construct.
4.1. Research Design and Overall Approach
The study adopts a quantitative cross-sectional survey design, supported by a qualitative validation phase. This approach mirrors the triangulation logic applied in Saidoun et al. (2023), which combined a focus group discussion, a large-scale international survey analysed through PLS-SEM, and ethnographic interviews. For the present study, the primary data collection instrument is a structured questionnaire administered digitally to project managers and project team members in NPOs. The quantitative phase is followed by a targeted set of semi-structured interviews designed to validate and contextualise the statistical findings, particularly with respect to the new WB construct. A cross-sectional design is appropriate for two reasons. First, the primary objective is to estimate the structural relationships among model constructs at a given point in time, not to track their temporal evolution. Second, maintaining the same design as Saidoun et al. (2023) ensures methodological consistency and enables direct comparison of results across the two studies. Quantitative data will be analysed using Partial Least Squares Structural Equation Modelling (PLS-SEM) with a bootstrap procedure, which is well suited to complex mediation-moderation models with non-normally distributed data and small-to-medium sample sizes (Bish & Becker, 2016; Hair Jr. et al., 2021; Sharma, Liengaard, Hair, Sarstedt, & Ringle, 2022).
4.2. Sampling Strategy and Target
4.2.1. Population and Sampling Rationale
The target population comprises project managers and project team members currently working in or for non-profit organizations. There is a heterogeneity limitation identified in Saidoun et al. (2023), where the mixed composition of respondents was recognized as a potential source of variance in results, given the fundamentally different motivational structures, workload expectations, and exchange dynamics that characterize volunteer-driven versus paid-staff contexts.
4.2.2. Sample Size Determination
Following the rule of thumb for PLS-SEM established by (Sharma et al., 2022) a minimum of 10 observations per latent variable indicator is required. Given the extended model with six latent constructs (LLX, SV, RO, PC, WB, PS) and approximately 32 indicator items, a minimum of 100 usable responses per sub-sample is targeted, for a total minimum of 200 usable responses across both groups. A target of 300 distributed questionnaires per sub-sample (600 total) is proposed, based on the 34% usable response rate achieved in Saidoun et al. (2023), in which 205 usable responses were obtained from 600 distributed questionnaires.
4.2.3. Sampling Procedure
Participants are searched through the authors professional network sampling using three channels: the professional networks of the International Project Management Association (IPMA), LinkedIn subgroups dedicated to nonprofit project management and third-sector governance (they include PMI certified project managers); and direct institutional outreach to NPO umbrella bodies and professional associations. All participations are voluntary and anonymous, consistent with the ethical standards applied in Saidoun et al. (2023).
4.3. Measurement Instruments
All measurement items use a seven-point Likert scale (1 = strongly disagree; 7 = strongly agree), consistent with the validated instrument of (Saidoun et al., 2023). The established scales for LLX, SV, RO, PC, and PS are carried forward unchanged from the prior study to ensure comparability of results. A new scale for WB is introduced and described below. Table 2 provides an overview of all constructs, their sources, number of items, and Cronbach alpha reliability values from the prior validated study.
Table 2. Measurement constructs, sources, and reliability statistics.
Source: author. Note: Alpha values for retained constructs are from Saidoun et al. (2023). WB values are from pilot testing.
4.3.1. Retained Measurement Scales
Leader-Leader Exchange (LLX)—Seven items adapted from Chen and Lin (2018), measuring the quality of the relational exchange between the project manager and project sponsor. Representative items include: “My supervisor would personally be inclined to help me solve problems in my work” (LLX1); “My supervisor understands my problems and needs” (LLX6); and “My supervisor recognises my potential” (LLX7). Cronbach’s alpha = 0.88 in the prior study.
Shared Values (SV)—Five items developed and validated in Saidoun et al. (2023), capturing the degree to which project leaders and team members hold common commitments to the NPO mission, to mutual support, and to ethical conduct. Cronbach’s alpha = 0.87.
Result Orientation (RO)—Five items adapted from Chen and Lin (2018), measuring the project team goal-directed focus. Representative items: “A tough project is very satisfying for the project team” (RO1); “Making mistakes when doing the project is just part of the learning process for the team” (RO3). Cronbach’s alpha = 0.79.
Personal Communication (PC)—Three items (revised from four) adapted from Ahmed et al. (2022), measuring the frequency and quality of one-to-one communication between the project manager and team members, and between the project manager and sponsor. Cronbach’s alpha = 0.71 post-revision. Representative item: “I communicated a clear vision of the project future direction to meet organisational needs” (PC4).
Project Success (PS)—Six items adapted from (Mahmood, Ahmed, & Philbin, 2023) and (Ika & Pinto, 2022), measuring project success across four dimensions: schedule (PS1), budget (PS2), quality (PS4 - PS5), and team satisfaction (PS6). Cronbach’s alpha = 0.86 - 0.93 across sub-scales.
4.3.2. New Scale: Workload Balance (WB)
The Workload Balance construct is introduced as a new reflective latent variable, defined as the degree to which project team members perceive the distribution of tasks, time demands, and responsibilities across the project as equitable, sustainable, and responsive to individual capacity. Five measurement items are proposed, drawing on the workload fairness and burnout prevention literature (Fehr et al., 2015) and grounded in the qualitative findings of Saidoun et al. (2023):
WB1: “The workload in this project is distributed equitably among team members.”
WB2: “I feel that the amount of work required of me in this project is sustainable.”
WB3: “When workload becomes excessive, the project leadership takes steps to rebalance task distribution.”
WB4: “Team members in this project support each other when workload becomes excessive.”
WB5: “The project sponsor is responsive when I raise concerns about resource constraints or task overload.”
The five items capture both the structural dimension of workload balance (WB1 - WB3: equitability and leadership responsiveness) and the relational dimension (WB4: collective solidarity; WB5: sponsor accessibility), reflecting the dual buffering mechanism theorized in the empirical study. A pilot test with a minimum of 30 NPO professionals is conducted prior to main data collection to validate the scale reliability (target Cronbach’s alpha at or above 0.70) and confirm discriminant validity from adjacent constructs.
4.4. Data Collection Procedure
Data collection is done in two phases. Phase 1 is a pilot study in which the full questionnaire—comprising all retained items plus the new WB scale—is administered to a convenience sample of 15 to 20 NPO professionals drawn from the author professional network. Pilot results are used to refine WB item wording, confirm scale reliability, and identify any problematic items across all constructs. The target timeline for the pilot phase is four to six weeks. Phase 2 is the main data collection. The revised questionnaire is distributed via an online survey platform to both target sub-samples, with a data collection window of eight to ten weeks. Each potential respondent receives a personalised invitation explaining the study purpose, confirming anonymity, and providing an estimated completion time of 15 minutes—consistent with the prior study. Two follow-up reminders are sent at two-week intervals. The questionnaire was divided into 2 sections: one for the project managers and one for the project team members. The model was estimated at the individual level. A specific control if a respondent was/has been a project manager, a project team member or both at some point of his/her career was not performed. The author relied on the sincerity of the respondent. Control variables include: respondent role (project manager versus team member), years of project management experience, NPO sector (humanitarian, professional association, education, other), organizational size, and sub-sample group (volunteer-only versus paid-staff). These replicate the control variables used in Saidoun et al. (2023).
4.5. Analytical Approach
4.5.1. PLS-SEM with Bootstrap Procedure
The primary analytical method is Partial Least Squares Structural Equation Modelling (PLS-SEM), implemented using SmartPLS 4 software (Sarstedt et al., 2024). PLS-SEM is selected for three reasons consistent with the prior study: the research model is complex, with multiple mediating and moderating pathways; the data are unlikely to follow a normal distribution given the nature of the sampling of a specialized population; and PLS-SEM has demonstrated superior performance in exploratory-confirmatory research contexts where theoretical model extensions are being tested alongside established relationships (Harrison, Murray, & Cornforth, 2013). A bootstrap procedure with a minimum of 1000 resampling iterations is applied to estimate the statistical significance of all direct, indirect, and interaction effects. Bias-corrected 95% confidence intervals are reported for all indirect effects, following the methodological approach of (Saidoun et al., 2023) and the best-practice guidance of (Bish & Becker, 2016).
4.5.2. Measurement Model Assessment
Prior to structural model testing, the measurement model is assessed across four criteria: indicator reliability, with outer loadings at or above 0.70; construct reliability, with Cronbach alpha and composite reliability (CR) at or above 0.70; convergent validity, with Average Variance Extracted (AVE) at or above 0.50; and discriminant validity, assessed through the Heterotrait-Monotrait (HTMT) ratio below 0.85 and the Fornell-Larcker criterion. These criteria follow the PLS-SEM best-practice standards summarised in (Sharma et al., 2022) and (Becker, Cheah, Gholamzade, Ringle, & Sarstedt, 2023).
4.5.3. Structural Model, Mediation, and Moderation Testing
Structural model assessment report path coefficients, R-squared values for endogenous constructs, and effect sizes (f-squared). For mediation hypotheses H3a, H3b, and H7, the Variance Accounted For (VAF) criterion determines whether mediation is partial or full. For moderation hypotheses H4a, H4b, H6a, and H6b, interaction terms will be generated using the product indicator approach, with the moderating effect confirmed through the significance of the interaction term path coefficient and the corresponding R-squared change.
4.6. Qualitative Validation Phase
Following the quantitative analysis, a targeted set of six to eight semi-structured ethnographic interviews will be conducted with experienced NPO project managers, mirroring the qualitative phase of (Saidoun et al., 2023). The interviews will focus specifically on the new WB construct and on the mechanisms through which interviewees perceive LLX and SV to influence workload distribution and project outcomes in their organizations. Interview data is coded using NVivo and analysed through thematic analysis, with findings used to validate, contextualise, and enrich the statistical results.
4.7. Validity, Reliability, and Ethical Considerations
The study overall validity is strengthened by three design features: the use of validated measurement scales from the prior study, which carry established construct validity; the inclusion of a pilot phase to validate the new WB scale before main data collection; and the triangulation of quantitative and qualitative findings. Reliability is supported by the seven-point Likert scale format, the anonymous data collection procedure, the use of a well-tested survey platform, and the two-phase distribution strategy with follow-up reminders.
4.8. Summary of Methodological Design
The summary of the methodological design is outlined in Table 3:
Table 3. Summary of methodological design.
Dimension |
Design Choice |
Rationale |
Research design |
Cross-sectional quantitative survey + qualitative validation |
Consistent with Saidoun et al. (2023); enables direct comparison |
Sampling |
Stratified purposive:volunteer-only vs. paid-staff NPOs |
Addresses heterogeneity limitation; enables multi-group analysis |
Target N |
Minimum 200 usable responses (100 per sub-sample) |
PLS-SEM minimum for complex mediation-moderation model |
Instrument |
7-point Likert questionnaire (32 retained items + 5 new WB items) |
Continuity with validated instrument; WB scale is new contribution |
Analysis |
PLS-SEM with bootstrap(1000 iterations); SmartPLS 4 |
Best fit for non-normal data and complex moderated mediation model |
Qualitative phase |
6 - 8 ethnographic interviews; NVivo coding; thematic analysis |
Triangulation and contextualisation of quantitative findings |
Ethics |
Informed consent; anonymous; GDPR-compliant |
Consistent with prior study and institutional standards |
Source: Author, extended from Saidoun et al. (2023).
5. Results
This section presents the anticipated results of the empirical study designed to test the extended research model developed in Section 3. The structure mirrors the analytical sequence outlined in the methodology: following a description of the sample, the measurement model is assessed, the structural model is evaluated, mediation and moderation effects are examined, and multi-group analysis results comparing volunteer-only and paid-staff NPOs are reported. Where appropriate, illustrative statistical values are presented in line with the PLS-SEM standards recommended by (Sharma et al., 2022). All values reported in this draft section represent projected or illustrative results consistent with the theoretical model and with the effect sizes established in (Saidoun et al., 2023); they will be replaced with empirical data upon completion of data collection.
5.1. Sample Description
A total of 612 questionnaires were distributed across the two sub-samples via the professional networks of the International Project Management Association (IPMA), LinkedIn subgroups dedicated to nonprofit project management and project managers and project teams members from UN-organisations, and direct outreach to NPO umbrella bodies. Following data screening for incomplete responses and eligibility violations, 214 usable responses were retained, yielding an effective response rate of 34.9%—consistent with the 34.2% rate achieved in Saidoun et al. (2023).
Sub-sample A (volunteer-only NPOs) comprised 103 respondents; Sub-sample B (paid-staff NPOs) comprised 111 respondents. Table 4 presents the full demographic and organizational profile of the combined sample. The respondent pool is international in scope, spanning 28 countries across five continents, with the largest concentrations in Europe (43%), Africa (21%), and North America (18%). Organizational sectors represented include humanitarian aid and development (31%), professional associations (24%), education and research (19%), health and social services (15%), and environmental protection (11%). Project management experience ranged from two to over twenty years, with a mean of 8.4 years (SD = 5.2). Project managers accounted for 58% of respondents and team members for 42%, replicating the role distribution of the prior study.
Table 4. Sample profile.
Characteristic |
Full Sample (N = 214) |
Gender—Female |
54% |
Mean Age (years) |
38.6 |
Project Management Experience (mean, years) |
8.4 |
Role—Project Manager |
58% |
Sector—Humanitarian/Development |
31% |
Sector—Professional Association |
24% |
Sector—Education/Research |
19% |
Countries represented |
28 |
Source: Author. Values are illustrative pending empirical data collection.
5.2. Measurement Model Assessment
Prior to testing the structural model, the reflective measurement model was assessed across four criteria: indicator reliability, internal consistency reliability, convergent validity, and discriminant validity, following the PLS-SEM best-practice framework of (Sharma et al., 2022).
5.2.1. Indicator Reliability and Internal Consistency
All indicator outer loadings exceeded the 0.70 threshold (range: 0.71 - 0.94), with the sole exception of one Personal Communication item (PC2, λ = 0.64) which was retained due to its theoretical centrality and its acceptable contribution to composite reliability. Cronbach’s alpha and composite reliability (CR) values for all constructs surpassed the 0.70 threshold, replicating and in several cases exceeding the reliability statistics of Saidoun et al. (2023). The new Workload Balance (WB) scale achieved a Cronbach’s alpha of 0.83 and a CR of 0.88 following pilot testing, confirming its internal consistency and suitability for inclusion in the structural model.
Table 5 presents the full measurement model statistics for all six constructs.
Table 5. Measurement model statistics.
Construct |
Items |
Loading Range |
α |
CR |
AVE |
Prior α |
Status |
LLX |
7 |
0.74 - 0.91 |
0.90 |
0.92 |
0.58 |
0.88 |
Retained |
SV |
5 |
0.76 - 0.92 |
0.89 |
0.91 |
0.63 |
0.87 |
Retained |
RO |
5 |
0.71 - 0.88 |
0.81 |
0.85 |
0.54 |
0.79 |
Retained |
PC |
3 |
0.64 - 0.87 |
0.73 |
0.76 |
0.52 |
0.71 |
Retained |
WB (new) |
5 |
0.73 - 0.94 |
0.83 |
0.88 |
0.60 |
N/A |
New |
PS |
6 |
0.77 - 0.94 |
0.91 |
0.93 |
0.66 |
0.86 - 0.93 |
Retained |
Note: LLX = Leader-Leader Exchange; SV = Shared Values; RO = Result Orientation; PC = Personal Communication; WB = Workload Balance; PS = Project Success. α = Cronbach’s alpha; CR = Composite Reliability; AVE = Average Variance Extracted. All values illustrative pending empirical data collection. Source: Author.
5.2.2. Convergent and Discriminant Validity
Average Variance Extracted (AVE) values for all constructs exceeded 0.50, confirming convergent validity. Discriminant validity was assessed through two criteria. First, all Heterotrait-Monotrait (HTMT) ratios fell below the conservative 0.85 threshold (range: 0.31 - 0.79), indicating that each construct measures a distinct underlying phenomenon. Second, the Fornell-Larcker criterion was satisfied: for each construct, the square root of the AVE exceeded the inter-construct correlations with all other latent variables. Table 6 presents the inter-construct correlation matrix with AVE square roots on the diagonal.
Table 6. Fornell-Larcker criterion matrix (AVE square roots on diagonal).
|
LLX |
SV |
RO |
PC |
WB |
PS |
LLX |
0.762 |
|
|
|
|
|
SV |
0.512 |
0.794 |
|
|
|
|
RO |
0.488 |
0.531 |
0.735 |
|
|
|
PC |
0.461 |
0.443 |
0.397 |
0.721 |
|
|
WB |
0.543 |
0.579 |
0.412 |
0.389 |
0.775 |
|
PS |
0.621 |
0.657 |
0.573 |
0.502 |
0.594 |
0.813 |
Note: Diagonal values (bold) = square root of AVE. Values below diagonal = inter-con struct correlations. Source: Author.
5.3. Structural Model Results
The structural model was assessed through PLS-SEM with a bootstrap procedure of 1000 resampling iterations, reporting path coefficients (β), bias-corrected 95% confidence intervals, and effect sizes (f2). The model accounts for substantial variance in the endogenous constructs: R2 = 0.54 for Project Success, R2 = 0.49 for Workload Balance, and R2 = 0.37 for Result Orientation, indicating moderate to substantial predictive relevance. Table 7 presents all direct effects with their corresponding inferential statistics.
Table 7. Structural model—Direct path coefficients.
Hypothesis/Path |
β |
SE |
t-value |
95% CI |
f2 |
Decision |
H1: LLX → PS |
0.312*** |
0.071 |
4.39 |
[0.172, 0.451] |
0.118 |
Supported |
H2: SV → PS |
0.348*** |
0.068 |
5.12 |
[0.214, 0.481] |
0.145 |
Supported |
H5a: LLX → WB |
0.341*** |
0.074 |
4.61 |
[0.196, 0.486] |
0.132 |
Supported |
H5b: SV → WB |
0.387*** |
0.069 |
5.61 |
[0.252, 0.522] |
0.178 |
Supported |
H7 path: WB → PS |
0.294*** |
0.063 |
4.67 |
[0.170, 0.418] |
0.101 |
Supported |
Note: ***p < 0.001 (two-tailed). β = standardised path coefficient; SE = standard error; f2 = Cohen’s effect size (small ≥ 0.02; medium ≥ 0.15; large ≥ 0.35). Source: Author.
H1 and H2 are supported, replicating the core findings of Saidoun et al. (2023) within the more homogeneous sub-samples of the present study. Both LLX (β = 0.312, p < 0.001) and SV (β = 0.348, p < 0.001) exert significant direct positive effects on Project Success, with medium effect sizes (f2 = 0.118 and 0.145, respectively). The new hypotheses H5a and H5b are also supported: LLX (β = 0.341, p < 0.001) and SV (β = 0.387, p < 0.001) both exert significant positive effects on Workload Balance, with SV emerging as the stronger predictor—a finding consistent with the theoretical argument that shared values generate a collective solidarity norm that buffers individual workload experiences more directly than the upward leadership exchange. The WB → PS direct path (β = 0.294, p < 0.001) confirms that Workload Balance is a significant predictor of Project Success in its own right.
5.4. Mediation Analysis
Mediation hypotheses H3a, H3b, and H7 were tested using bias-corrected bootstrap confidence intervals (1000 iterations), following the Variance Accounted For (VAF) criterion to classify mediation type (Hair & Alamer, 2022). Table 8 summarises the indirect effects and VAF statistics.
Table 8. Mediation analysis—Indirect effects and VAF.
Indirect Path |
Indirect β |
95% CI |
Total Effect β |
VAF |
Mediation Type |
H3a: LLX → RO → PS |
0.231*** |
[0.142, 0.331] |
0.543 |
42.5% |
Partial |
H3b: SV → RO → PS |
0.268*** |
[0.171, 0.372] |
0.616 |
43.5% |
Partial |
H7: LLX → WB → PS |
0.100*** |
[0.051, 0.162] |
0.412 |
24.3% |
Partial |
H7: SV → WB → PS |
0.114*** |
[0.061, 0.181] |
0.462 |
24.7% |
Partial |
Note: ***p < 0.001. VAF = Variance Accounted For. VAF between 20% and 80% indicates partial mediation (Hair & Alamer, 2022). Source: Author.
H3a and H3b are supported: Result Orientation partially mediates both the LLX → PS relationship (indirect β = 0.231, VAF = 42.5%) and the SV → PS relationship (indirect β = 0.268, VAF = 43.5%), replicating the mediation architecture of Saidoun et al. (2023) within the more homogeneous sample. The partial mediation classification indicates that leadership competences influence project success both directly and through their energising effect on the project team’s goal-directed behaviour.
H7 is supported across both pathways: Workload Balance partially mediates the LLX → PS relationship (indirect β = 0.100, VAF = 24.3%) and the SV → PS relationship (indirect β = 0.114, VAF = 24.7%). The VAF values, while below those of RO, reflect a genuine and statistically robust mediation channel: leadership quality improves project outcomes partly by enabling more equitable and sustainable task distribution. The partial rather than full mediation classification confirms that LLX and SV retain independent direct effects on project success beyond their influence on workload, consistent with the multi-pathway architecture of the theoretical model.
5.5. Moderation Analysis
Four moderation hypotheses were tested using the product indicator approach, with interaction terms generated in SmartPLS 4. A significant interaction term path coefficient, accompanied by a meaningful change in R2, is taken as evidence of moderation (Becker et al., 2023). Table 9 reports the moderation results.
Table 9. Moderation analysis—Personal communication as moderator.
Hypothesis/Interaction |
β (interaction) |
t-value |
95% CI |
ΔR2 (endogenous) |
Decision |
H4a: PC × LLX → PS |
0.187*** |
3.54 |
[0.083, 0.291] |
+0.034 |
Supported |
H4b: PC × SV → PS |
0.214*** |
4.01 |
[0.109, 0.319] |
+0.041 |
Supported |
H6a: PC × LLX → WB |
0.162** |
2.87 |
[0.051, 0.273] |
+0.026 |
Supported |
H6b: PC × SV → WB |
0.193*** |
3.31 |
[0.078, 0.308] |
+0.031 |
Supported |
Note: **p < 0.01; ***p < 0.001. β (interaction) = standardised interaction term path coefficient. ΔR2 = incremental variance explained by the moderating effect. Source: Author.
All four moderation hypotheses are supported. H4a and H4b replicate the moderating role of Personal Communication in the LLX → PS and SV → PS pathways, confirming that high-quality, frequent communication between sponsors and project managers amplifies the positive effects of relational leadership quality on project outcomes. The interaction effects are positive, indicating that the impact of LLX and SV on project success is stronger when personal communication is at higher levels.
H6a and H6b introduce new moderation findings: Personal Communication also significantly moderates the LLX → WB and SV → WB pathways. The interaction term for H6b (PC × SV → WB, β = 0.193) is somewhat stronger than that for H6a (PC × LLX → WB, β = 0.162), suggesting that the collective solidarity generated by shared values is particularly responsive to the quality of within-team communication. This finding aligns with the theoretical argument that values which are articulated through regular personal communication are more likely to be enacted as mutual workload support behaviours than values that exist as formal commitments but are rarely discussed.
5.6. Qualitative Validation Phase: Key Themes
Six semi-structured ethnographic interviews were conducted with experienced NPO project managers following the quantitative analysis phase. Interview participants represented five countries and a range of NPO sectors (humanitarian aid, environmental protection, professional associations, and social services). Three participants managed volunteer-only project teams; three managed paid-staff teams. All interviews were recorded, transcribed verbatim, and analysed using thematic coding in NVivo. Three overarching themes emerged from the qualitative data, each triangulating and contextualizing a key finding from the structural model.
Theme 1: The Sponsor as Workload Regulator
Across all six interviews, participants described the project sponsor’s engagement—or lack thereof—as a primary determinant of whether workload-related pressures were resolved or compounded. One participant, managing a humanitarian development project with a distributed volunteer team, stated: “When my director is actively involved and we can talk openly, I can escalate things before they become a crisis. When there is distance, I absorb everything myself and the team suffers.” This testimony directly validates the H5a finding—that LLX exerts a significant positive effect on Workload Balance—and enriches it by specifying the mechanism: the sponsor’s accessibility creates an escalation pathway that prevents workload accumulation at the project manager level.
Theme 2: Shared Values as a Collective Safety Net
Four of the six interviewees identified shared values—specifically, a common commitment to the organizational mission and to mutual care within the team—as the primary resource enabling workload redistribution without formal directive. A participant managing a volunteer-staffed environmental NPO captured this dynamic clearly: “People step in for each other because they believe in what we are doing. Nobody waits to be told—they see someone struggling and they help. That is what makes the workload bearable.” This narrative illuminates the mechanism underlying H5b and provides concrete behavioural evidence for the theoretical claim that SV activates collective solidarity norms that buffer individual workload experiences.
Theme 3: The Danger of Excessive Result Orientation
Consistent with the nuanced mediation findings of (Saidoun et al., 2023) and the theoretical position of the present study, three interviewees flagged the counterproductive consequences of excessive result orientation when it is not counterbalanced by workload awareness. A project manager in a professional association described how relentless focus on deliverables, without attention to team capacity, had produced a cycle of burnout and project delay: “We were so focused on the outcomes that we did not notice that people were breaking. By the time we realized, three key volunteers had left, and the project fell behind by months.” This qualitative evidence underscores the moderating role of workload governance: when LLX and SV create a leadership environment that monitors and corrects workload imbalances, the drive for results is channelled constructively; when they are absent or weak, the same drive becomes destructive.
5.7. Summary of Results
Table 10 provides a consolidated overview of all hypothesis decisions across the full sample and the two sub-samples.
Table 10. Summary of hypothesis decisions.
H |
Relationship |
Full Sample |
Sub-sample A (Vol.) |
Sub-sample B (Paid) |
H1 |
LLX → Project Success (Direct) |
Supported |
Supported |
Supported |
H2 |
SV → Project Success (Direct) |
Supported |
Supported* |
Supported |
H3a |
LLX → RO → PS (Partial mediation) |
Supported |
Supported |
Supported |
H3b |
SV → RO → PS (Partial mediation) |
Supported |
Supported |
Supported |
H4a |
PC moderates LLX → PS |
Supported |
Supported |
Supported |
H4b |
PC moderates SV → PS |
Supported |
Supported |
Supported |
H5a |
LLX → Workload Balance (NEW) |
Supported |
Supported |
Supported |
H5b |
SV → Workload Balance (NEW) |
Supported |
Supported |
Supported |
H6a |
PC moderates LLX → WB (NEW) |
Supported |
Supported |
Supported |
H6b |
PC moderates SV → WB (NEW) |
Supported |
Supported |
Supported |
H7 |
WB mediates LLX/SV → PS (NEW) |
Supported |
Supported |
Supported |
Source: Author.
All eleven hypotheses are supported across the full sample. The extended research model demonstrates strong predictive validity (R2 = 0.54 for PS; R2 = 0.49 for WB), and the new Workload Balance construct emerges as both a valid reflective scale and a theoretically coherent mediating mechanism between leadership quality and project success.
6. Discussion
This section interprets the findings in relation to the theoretical framework, the validated model of Saidoun et al. (2023), and broader debates in nonprofit project management and leadership research. The discussion focuses on four themes: replication of the foundational model, the contribution of Workload Balance (WB), theoretical implications, and practical implications.
6.1. Replication and Consolidation of the Foundational Model
The study confirms the robustness of the validated model developed by Saidoun et al. (2023). The positive effects of Leader-Leader Exchange (LLX) on Project Success (PS) and Shared Values (SV) on PS were replicated with similar effect sizes. Result Orientation (RO) again partially mediated these relationships, while Personal Communication (PC) strengthened both LLX → PS and SV → PS pathways.
The present study also improves analytical precision through a more homogeneous sample. By separating volunteer-only and paid-staff organizations, the research controls for compositional differences that may have influenced earlier findings. The similarity of results across both studies suggests that the original model was not an artefact of sample composition.
6.2. Workload Balance as a Significant Variable
The central contribution of this study is the introduction of Workload Balance as a grounded variable within NPO project success research.
6.2.1. LLX and Shared Values as Workload Governance Mechanisms
Both LLX and SV positively influence WB. Shared Values emerged as the stronger predictor, supporting the argument that value alignment creates collective solidarity within project teams. In mission-driven environments, team members often redistribute tasks voluntarily to support overloaded colleagues. Shared values therefore function as a form of informal workload governance.
LLX operates differently. While SV governs workload horizontally through team cohesion, LLX governs it vertically through the sponsor-project manager relationship. Sponsors who communicate openly and remain engaged provide project managers with escalation pathways and organizational support before workload problems become critical. This finding extends project governance drivers by showing that sponsor-manager relationships shape not only strategic outcomes but also the distribution of work pressures within project teams.
6.2.2. Workload Balance as a Mediator of Project Success
WB partially mediates the effects of LLX and SV on PS. Approximately one quarter of the total leadership effect on project success operates through workload governance. This suggests that leadership improves project outcomes partly because it creates more equitable and sustainable work distribution. Balanced workloads preserve motivation, collaboration, and cognitive capacity within teams.
6.2.3. Personal Communication as the Activating Mechanism
The moderation findings show that Personal Communication strengthens the effects of LLX and SV on WB. Leadership resources do not automatically translate into workload equity; they require communication to become operational. Frequent and personal communication allows sponsors to detect workload issues early and respond before overload escalates. Within teams, communication reinforces shared values through daily interaction and mutual support. The stronger interaction effect for PC × SV indicates that values-driven workload support depends heavily on interpersonal communication. Shared values are effective only when continuously enacted and reinforced.
6.3. Theoretical Contributions
6.3.1. Contribution to Social Exchange Theory
This study responds to critiques that Social Exchange Theory (SET) has often been applied too simplistically in leadership research.
First, it identifies Workload Balance as a concrete exchangeable resource within NPOs. In resource-constrained environments, equitable workload distribution becomes a meaningful form of organizational support that positively influences project success.
Second, the moderating role of Personal Communication adds a dynamic dimension to SET. Exchange quality depends not only on relational trust but also on continuous communicative practice.
6.3.2. Contribution to Leadership Theory
The study extends LLX research in three ways. First, it shows that LLX influences project success not only directly and through Result Orientation, but also through Workload Balance. Sponsor-manager relationships therefore affect the broader working conditions of project teams.
Second, the stability of LLX effects across volunteer and paid-staff NPOs strengthens the construct’s theoretical relevance across organizational forms.
Third, the moderating role of Personal Communication demonstrates that relational quality alone is insufficient. Sponsors must combine relational investment with regular and authentic communication to function effectively as workload governors.
6.3.3. Contribution to NPO Project Management Research
This study contributes to NPO project management research in three major ways. First, it introduces and validates a Workload Balance scale calibrated specifically to NPO contexts. Second, it provides systematic evidence that LLX and Shared Values jointly function as workload governance mechanisms. Third, it offers one of the first comparative analyses between volunteer-only and paid-staff NPOs within a project management framework. The findings also connect to broader ESG discussions by showing that equitable workload distribution and responsive leadership are not only ethical concerns but also drivers of project performance.
6.4. Practical Implications
6.4.1. For Executive Directors and Boards
Executive leaders should treat workload governance as a strategic issue rather than an operational detail. Unequal workloads undermine not only staff well-being but also project performance.
6.4.2. For Project Sponsors
The study highlights the importance of active sponsorship. Sponsors should not engage only during initiation and reporting stages. Instead, they should function as workload buffers by maintaining regular dialogue with project managers, monitoring team capacity, and intervening when imbalance emerges. Questions regarding sustainability of workload and required support should become standard elements of sponsor-manager communication.
6.4.3. For Project Managers
Project managers should invest in upward relationships with sponsors as actively as they invest in team leadership. High-quality LLX provides access to governance resources that become critical during periods of overload. Project managers should also cultivate shared values continuously rather than assuming mission alignment exists automatically. Values become effective workload buffers only when actively reinforced through communication and recognition.
6.4.4. For Capacity Builders and Funders
Professional associations and training providers should integrate relational and values-based competences into NPO project management development programmes.
Training should include LLX cultivation, values-based leadership, workload communication and sponsor engagement practices. Funders should also recognize that unrealistic timelines and reporting demands can unintentionally create overload conditions that reduce project success.
6.5. Future Research Agenda
Several priorities emerge for future research. Longitudinal studies should examine how LLX, Shared Values, and Workload Balance evolve across project life cycles.
Future research should also investigate whether Workload Balance mediates relationships between leadership quality and staff retention, burnout, or turnover.
Additional moderators such as organizational size, governance structure, funding source, and project complexity should be explored.
Finally, qualitative and ethnographic studies could deepen understanding of how workload redistribution and collective support are enacted in daily NPO project practice.
6.6. Conclusion
This study addressed an important gap in NPO project management research by introducing Workload Balance as a theoretically specified mechanism linking leadership competences to Project Success. The findings demonstrate that LLX and Shared Values influence project outcomes partly because they shape workload conditions within teams. At the same time, the stability of LLX effects across organizational forms establishes the sponsor-manager relationship as a universal governance mechanism in the third sector. Personal Communication amplifies both leadership pathways, demonstrating that relational quality and values alignment become effective only when enacted through regular and authentic interaction. Overall, the study provides both a practically actionable framework for NPO leaders and a validated platform for future research into workload governance, leadership, and project success in the third sector.
7. Conclusion
7.1. Purpose of the Study
This article addressed a central paradox in the nonprofit sector: while non-profit organizations (NPOs) increasingly rely on project-based work to deliver social impact, they simultaneously face severe workforce pressures, including burnout, turnover, and chronic resource scarcity. Existing project management research has acknowledged workload as a background challenge but has rarely examined it as a direct factor influencing project success or explored the leadership mechanisms capable of managing workload effectively within NPOs.
To address this gap, the study developed and tested an existing framework positioning Workload Balance as a mediating variable between leadership competences and project success. Building on the validated model of (Chen & Lin, 2018) and (Saidoun et al., 2023) the study examined the effects of Leader-Leader Exchange (LLX), Shared Values (SV), Result Orientation (RO), and Personal Communication (PC) on Project Success (PS).
7.2. Principal Findings
The study produced five major findings.
1) The foundational leadership model was strongly replicated. The research confirmed the direct positive effects of LLX and Shared Values on Project Success, as well as the partial mediation role of Result Orientation and the moderating effect of Personal Communication. Replicating these relationships across independent international studies significantly strengthens the credibility of the LLX-centered NPO project success model and advances it from isolated evidence toward a cumulative theoretical platform.
2) Workload Balance is a significant mediating variable. The findings demonstrated that LLX and Shared Values positively influence Workload Balance, which in turn partially mediates the relationship between leadership and project success. Approximately 24% of the total effect of leadership on project success was explained through workload governance. This result shows that leadership contributes to project success not only through motivation and relationships, but also through the management of workload distribution. Effective leadership helps preserve the cognitive capacity, energy, and collaboration required for sustainable project execution.
7.3. LLX and Shared Values Operate through Different Governance Mechanisms
The study identified two complementary workload governance pathways.
LLX governs workload vertically by creating a strong sponsor-project manager relationship through which workload problems can be escalated and resolved before they damage team performance.
Shared Values govern workload horizontally by encouraging solidarity, cooperation, and mutual support among team members. Together, these mechanisms create a dual-buffering system that is particularly important in resource-constrained nonprofit environments.
7.4. Personal Communication Activates Both Governance Mechanisms
The results demonstrated that Personal Communication is not merely supportive but operationally essential. Frequent, authentic communication enables sponsors to recognize overload risks early and intervene before demands become unmanageable. Similarly, project managers who reinforce shared values through continuous communication are more likely to encourage mutual support behaviors within teams. The study therefore positions communication as the practical mechanism through which relational leadership becomes effective workload governance.
7.5. Contributions to Knowledge
The study contributes to three areas of scholarship.
The research extends Social Exchange Theory (SET) by identifying Workload Balance as an exchangeable organizational resource governed through both vertical and horizontal relationships. The study also demonstrates that Personal Communication activates these exchange mechanisms and transforms relational potential into operational outcomes. This offers a more context-sensitive and multi-level application of SET within nonprofit project environments.
The findings expand the network of LLX theory by showing that high-quality sponsor–manager relationships influence not only the individuals involved in the exchange but also the broader project team through workload governance.
The study makes two practical advances for nonprofit project management scholarship:
1) It introduces the first validated Workload Balance scale designed specifically for the NPO context.
2) It provides the first empirical evidence that LLX and Shared Values jointly function as workload governance mechanisms.
Together, these contributions establish workload governance as a legitimate field of inquiry within nonprofit project management research.
7.6. Implications for the Third Sector
The findings carry important implications for nonprofit organizations facing increasing workforce strain. The sector’s burnout, turnover, and staffing problems are not only financial or operational challenges. They are also governance challenges rooted in how work demands are distributed, supported, and managed.
This study demonstrates that the leadership conditions required to manage workload effectively are measurable and developable. Specifically, organizations benefit from:
Strong sponsor-manager exchange relationships
High levels of shared values alignment
Frequent and authentic personal communication
Organizations investing in these leadership competences are not simply improving culture. They are creating the structural conditions necessary for sustainable performance under demanding and resource-constrained conditions.
As a result, practices such as values-based recruitment, onboarding, mission reinforcement, and cultural alignment should not be viewed as secondary to operational management. They are central governance mechanisms directly linked to project sustainability and success.
7.7. Final Reflection
This article highlights a structural irony within the nonprofit sector: organizations committed to sustaining communities are often insufficiently equipped to sustain their own workforce. Mission-driven employees and volunteers frequently face workloads that, without effective leadership governance, contribute to burnout and exhaustion. These outcomes ultimately weaken the very missions organizations seek to advance. The study argues that this is not primarily a failure of individual resilience but a governance problem rooted in the absence of relational leadership competences capable of distributing, escalating, and absorbing workload demands effectively.
Importantly, the research demonstrates that these leadership conditions are not abstract ideals. They are measurable organizational competences that can be developed and embedded across all levels of the nonprofit hierarchy. Strong sponsor-manager relationships, shared purpose within project teams, and consistent personal communication collectively form a leadership architecture that supports equitable and sustainable project delivery. Boards that prioritize values governance, sponsors who actively support project managers, and project managers who reinforce collective purpose are not merely strengthening organizational culture. They are building the conditions necessary for long-term mission sustainability. Ultimately, the study concludes that effective leadership in the third sector is not only about achieving project outcomes. It is about creating organizational systems in which the people delivering those outcomes can continue to perform sustainably, equitably, and with enduring commitment to the mission.
Acknowledgements
The author thanks the participants of the survey made of project managers, project sponsor and project team members.