The signing of the Convention on the protection of the Alps (also called Alpine Convention) by the Alpine States in 1991 heralded new practices and perspectives. This transnational project is intended to solve important social and ecological challenges faced by the Alpine population, i.e. motorized traffic, ageing of the population, national fragmentation of politics, climate change, etc. Convinced that the Alpine Convention should fulfill its potential, some non-governmental organizations and some particularly active persons created several networks of local political actors to connect local representatives, researchers, managers of protected areas and ecological associations. These were designed to realize what the Alpine Convention was promising: a sustainable pan-Alpine region. This thesis endeavours to understand how and why local political actors, organized in pan-Alpine networks, chose to take mountain regions in general, and the Alps in particular, as the shared frame of reference for their involvement. It explores if and how a pan-Alpine identity detached from and/or combined with the more "traditional" national identities is developing among and enacted by local political actors engaged for the Alpine Convention. It also analyzes the nature and socio-political significance of local political actors' involvement in the newly constituted pan-Alpine networks.