AN EMPIRICAL FRAMEWORK OF CRITICAL SUCCESS FACTORS FOR PUBLIC CONSTRUCTION PROJECTS IN TANZANIA: THE MODERATING ROLE OF THE PROJECT’S EXTERNAL ENVIRONMENT

Public construction projects in Tanzania continue to face recurrent issues, including cost overruns of 25–61% and delays of up to 48 months. Despite being essential to the nation's growth, these projects continue to face these challenges. These challenges highlighted systemic flaws in planning, procurement, cash flow management, and stakeholder coordination. Although critical success factors (CSFs) have been the subject of research worldwide, Tanzania lacks an empirically validated framework that integrates internal project capabilities with external environmental variables. By identifying, ranking, and testing critical success factors (CSFs) in Tanzanian public construction projects and by investigating the moderating effect of the Project External Environment (PEE), this study addresses the identified gap. This research analyzes five CSF categories: Risk management, Project Planning and Management, Project Stakeholders, Project Procurement and Supply, and PEE. The research is guided by Resource-Based Theory and Stakeholder Theory. A quantitative cross-section survey design was adopted, using structured questionnaires administered to 200 professionals involved in public construction projects in Tanzania, yielding 165 valid responses from project managers, engineers, contractors, and government supervisors. Data were analyzed using SPSS through reliability tests, descriptive statistics, correlation analysis, multiple regression, and moderation analysis. The findings revealed that CSFs had a significant positive influence on project success, with management support, effective planning, and stakeholder coordination emerging as the strongest predictors. The results further showed that the external environment significantly moderated the relationship between CSFs and project success, indicating that favourable political, economic, regulatory, technological, and social conditions strengthened project outcomes, while adverse conditions weakened them. The findings offer practitioners and policymakers insights that may be put into action, with a particular emphasis on effective resource allocation, stakeholder involvement, risk management, and adaptive planning. Within Tanzania's construction industry, the framework provided is a useful tool that may increase efficiency, reduce waste, and enhance the implementation of sustainable project outcomes.