A Decision-Support Framework for Prioritizing Megaproject Challenges in the Middle East Using the Last Planner System

Megaprojects in the Middle East are characterized by their scale and complexity, making them vulnerable to numerous challenges that hinder project objectives. The last planner system (LPS) has emerged as an effective lean approach for improving planning reliability and workflow performance. The main objective of this study is to identify, evaluate, and prioritize the implementation challenges affecting megaprojects in the Middle East. A total of 42 challenges were identified and classified into five groups, including Technical, Managerial, Economic and Financial, Sustainability and Feasibility, and Operational and Environmental. The Probability Index (PI), Workflow Impact Index (WII), and Impact Index of the last planner system (IILPS) were determined through field surveys and hierarchically integrated using a proposed two-stage fuzzy model. In Stage 1, PI and WII were combined to determine the Challenge Criticality Index (CCI), which was subsequently integrated with IILPS in Stage 2 to determine the final Lean Effectiveness Index (LEI). Spearman’s rank correlation analysis revealed the strongest agreement between owners and contractors regarding the Workflow Impact Index, while benchmark comparison supported internal ranking consistency, and a five-expert assessment supported face validity and practical plausibility of the resulting priorities. The results indicate that the Managerial challenge group is the most significant group, recording the highest average LEI and containing 5 of the 10 highest-ranked challenges. The challenge related to delayed transfer of information, leading to misunderstandings and operational misalignment, ranked highest according to the proposed model and achieved the highest LEI among all identified challenges. Furthermore, 54.8% of the identified challenges were classified within the High or Very High LEI categories, indicating that more than half were classified as high-priority targets for LPS-oriented intervention according to the proposed model.