Purpose – The purpose of this paper wasto explore, using Critical Success Factors, project management approaches in successful Mega Construction Projects in developing countries. Design/methodology/approach – The research was basedoncase study inquiry strategy comprising ofthreecase studies,which incorporatedinterviews with project managers of the respective mega construction projects. Findings – Two major findings were identified. Firstly, the project management approaches that contribute to the success of Mega Construction Projects in developing countries are similar to those outlined in the literature, including; Clear project objectives, Senior management support, Stakeholders involvement and consultation, and Competent Project Team. Secondly, more specific project management approaches and Critical Success Factors within the context of developing countries were identifiedfrom the findings of the thesis, including; outsourcing and collaboration, organizational culture, and the attitude of local stakeholders. Research Delimitations – The research waslimited to mega construction projects in developing countries, and successful Mega Construction Projects achieving at least one of three overall objectives; project objectives, business objectives, and social and environmental objectives. Theoretical and Practical Implications–The study providedinsightoneffective project management approaches for Mega Construction Projects in developing countries.Thiswould allowpractitioners to get an insight onthe Critical Success Factors which drives the Mega Construction Projects towards successful completion in developing countries. Moreover, the thesis would also supportthem in cross comparing Effective Project Management Approaches in different developing regions. Besides that, the generation of new sets of Critical Success Factors had contributed to the theoretical aspects of the study.