Megaprojects are projects characterized by significant investments attracting a high level of public attention or political interest because of substantial direct and indirect impacts on community, environment and budgets[1]. They are usually characterized by high technical, organizational and managerial complexity and involve a huge number of stakeholders with different interests [2]. The latter is one of the major challenge in megaproject management due to the complexity of stakeholders’ interrelationships and different interests. This paper presents an analysis on 20 megaproject case studies belonging to different sectors, such as the energy, the transports and public services. The purpose is to gather useful insights from the practice in order to understand better how to manage internal and external stakeholders in megaprojects.