Today, the world is experiencing a major cycle of investment in infrastructure, which is essential for the development and prosperity of countries and societies. Management failures in infrastructure projects are widely known, and some of them involve the weak engagement of project stakeholders. The importance of stakeholder involvement as a key factor in the success of infrastructure projects is widely recognized. However, the literature provides few answers to the question of how this process manifests itself in projects. Some scholars have concluded that it is a complex and under-researched management process. The research questions aim to find out how practitioners perceive stakeholder engagement, who conducts activities and processes related to stakeholder engagement and in what ways, what organizational aspects influence the process, and how success is achieved in infrastructure projects. Initially, eight experienced experts involved in a whole range of (complex) infrastructure projects were interviewed, and later, four additional interviews were conducted for verification purposes. During the interviews, all aspects of stakeholder engagement were discussed in detail and a thematic analysis was conducted. Based on the analysis, success and failure factors related to the stakeholder engagement process were defined. As a result, a framework model for stakeholder engagement and infrastructure project success is presented based on three levels of management and three levels of project success.