Impact of Megaproject Governance on Mega Construction Project Success through moderating role of project complexity

This study explores the influence of megaproject governance (MPG) on the success of mega construction projects (MCPS) in Pakistan, with a specific focus on the moderating role of project complexity and the moderated moderation effect of the Project Management Office (PMO). Drawing on complexity theory, the research presents a multi-layered governance-performance framework and investigates how governance structures, mechanisms, and the external environment interact with project complexity and PMO capabilities to shape project outcomes. Using a sample of 327 respondents from large-scale residential, hydroelectric, road, and airport construction projects across Pakistan, data were analyzed through Partial Least Squares Structural Equation Modeling (PLS-SEM). The results confirm that MPG has a significant positive impact on MCPS; however, this relationship is negatively moderated by project complexity. Importantly, the presence of an effective PMO not only strengthens project governance practices but also mitigates the negative effects of complexity, thereby enhancing overall project performance. The originality of this study lies in its introduction of a moderated moderation model in the construction project management literature\u2014linking governance, complexity, and PMO functions within a single empirical framework. Unlike prior studies that examine these constructs in isolation, this research provides novel insights into how firm-level PMOs function as adaptive systems to manage interdependencies, uncertainties, and stakeholder dynamics in complex megaproject environments. From a practical perspective, the findings offer actionable guidance for policymakers, contractors, and project sponsors in emerging economies. Establishing strong governance mechanisms and institutionalizing PMOs can substantially improve planning, coordination, and risk management in large infrastructure projects. The study also proposes a PMO functional capability matrix to help organizations align governance practices with complexity factors, enabling more resilient and performance-driven project execution. These insights are particularly relevant for public sector infrastructure programs like Pakistan\u2019s PSDP, where delays, cost overruns, and stakeholder fragmentation are common challenges.