This introductory chapter shows how this Project was structured and developed along three major phases, which took place one after the other in most cases, but not exactly at the same time across countries, as many researchers actually joined the project at different times during its first years. The ICSEM Project was presented and launched at the end of the 4th EMES International Research Conference on Social Enterprise, which was held in Liege (Belgium) in early July 2013. It was suggested to use, as one among other tools, the three dimensions of the EMES “ideal type” of social enterprise—namely the nature of the social mission or social aims, the type of economic model and the governance structure—to inform the diversity of social enterprises. Most SE approaches share the view that social enterprises combine an entrepreneurial dynamic to provide services or goods with the primacy of a social mission.