Italy is one of the few countries with a law on social cooperatives and a law on social enterprises. Even though both laws seem quite similar, their levels of success have been drastically different. The understanding of the different outcomes of the two laws can help in evaluating the process of institutionalisation amongst social enterprises. This is the main aim of the present paper that starts by describing the process of institutionalisation of social cooperatives. It follows presenting data on the diffusion of social cooperatives, especially through looking at the stocks of existing social cooperatives, their characteristics and their social and economic impact. It describes the main characteristics of the new law on social enterprises and introduces the first data on their diffusion. It explains the reasons of the different levels of success of social cooperatives and social enterprises in Italy. Finally, the paper concludes with a brief discussion on the prospects and new challenges for social cooperatives and social enterprises.