The Economics of Public Private Partnerships Chair is a research group that gathers academics and practitioners from various institutions. Its aim is indeed to promote the development of a network of researchers and decision-makers interested in issues related to public services reforms. For two decades, the procurement of public services (like water supply, public transportation, waste disposal, and beyond, education, research and health, etc.) has been engaged in a process of intensive changes, both in developed and less-developed countries. Both at the local and national levels, public authorities have been willing to introduce new regulatory regimes and to modify the procurement procedures in order to allow private sector participation and improve performances. Thinking about those issues is high on the agenda of practitioners and policy-makers. At the same time, it has also generated a new stream of both theoretical and empirical research, which redefines our understanding of the limits between the public and the private spheres.