This paper focuses on the perspective of a transborder co-operation among the Adriatic regions. A stronger co-operation may be achieved by extending the existing Alpe Adria Agreement to those other Adriatic regions, which share the same problems and development goals. With this vision in mind, the political and economic motivations for transborder co-operation, as well as the most important European experiences, have been here analysed. In the last section the paper points out that an enlarged Alpe Adria may be very important both as a tool to lobby common interests and as a container of specific development projects for the Adriatic