While, in practice, the participation of private actors at the local and national government levels through various types of contractual agreements has been increasing over the last decades, there are still few studies on the functioning and performances of such relationships. Our aim is to highlight some significant theoretical and empirical issues concerning Public–Private Agreements. We first assess the potential sources of efficiency of such contractual agreements. We then examine the selection issue which is a crucial stage for the efficiency of such agreement. Finally, we stress the importance of the institutional framework showing how it might affect the agreements’ efficiency.