This report provides an overview of the roots, concept, legal evolution, numbers and eco-system of social enterprise in Belgium and the challenges it faces. In the first section, a number of roots and drivers are described that have paved the way for the current understanding and landscape of social enterprise in Belgium. These roots include the associative tradition, the cooperative movement, the tradition of mutuals, the (new) social economy and the more recent business-oriented approach. The role of public policies and philanthropic actors is also discussed. In the second section, the legal evolution of social enterprise is sketched out, and three main ideal types are identified based on their underlying dynamics: (i) the entrepreneurial approach to the general interest (typically embodied by associations and foundations); (ii) the combination of mutual and general interest (typically embodied by cooperatives and mutuals); and (iii) the more borderline case of businesses that combine private and general interest. In this section, the social purpose company framework is presented, as well as a number of certification schemes. In the third section on measuring social enterprises, two approaches are distinguished: bottom-up and inclusive. Figures are presented based on studies following each approach, with the inclusive approach providing the most comprehensive number of more than 18 000 social enterprises in Belgium. Figures on employment, growth rates, legal forms and activity sectors are also presented. The fourth section reviews the main actors in the social enterprise eco-system in Belgium and its various regions. Significant attention is devoted to public authorities and public policies at the federal and regional levels. Networks and federations of different types are also presented, as well as advice and consultancy organisations, universities, observatories, incubators, etc. Finally, the need for and supply of social finance are presented and the gaps between demand and supply are discussed. Finally, ...