Social entrepreneurship is commonly used to qualify all entrepreneurial initiatives that serve a social and/or environmental mission and that reinvest a large part of their surpluses in support of their mission. Although this defi- nition is not yet stabilised and its boundaries remain unclear, it focuses on the aim of achieving both economic efficiency and social purpose (Austin et al., 2006; Moulaert et al., 2013). It took place within a context of economic crisis and unemployement in the 1980s and of great uncertainty about the future of Welfare States and their capacity to meet new societal needs. The financial and budgetary constraints that most countries are facing force public authorities to develop new forms of interaction between public and private sectors and to build new responses to societal challenges that are sustainable, socially, economically and environmentally. Within this con- text, all sorts of initiatives that answer new social needs, often described as social innovations are gaining interest. Social entrepreneurship is often associated with social innovation since social entrepreneurs are searching for innovative solutions to meet these new needs. Recent works (Moulaert et al., 2013), in the continuation of the analyses realised in Québec (Klein, Harrisson, 2007), consider that social innovation “is not only a descriptor for a set of practices but an emerging phenomenon, a theoretical construct and an on- going field of research within a world of social transformation” (p. 2). Although interest in social entrepreneurship seems to be recent, the first works on social entrepreneurship are found in the 1980s. While social entrepreneurship is still a phenomenon not well bounded theoretically, it is becoming an important economic reality at a large scale, both in the US and in Europe, given its capacity to reconcile private and social value creation. This paper is structured as follows. The first section discusses the differ- ent notions used in the literature, sometimes indiscriminately, hiding some important differences and controversial issues. These notions are social entrepreneurship, social entrepreneur and social enterprise. The second section identifies the main elements of controversy between the different approaches to social entrepreneurship, social entrepeneur and social enter- prise that we have identified.