In current scientific and political discourses there is common agreement that the future of alpine agriculture is not only a challenge for farmers, but also for the whole society. What remains unclear is the question of how to adapt agriculture towards sustainable development of the alpine territory in a manner that takes sufficient account of local diversity. We propose to treat agriculture and rural development as a matter of local concern starting with a definition of sustainable agriculture drawn up by local stakeholders. Based on a three-year experiment, we examine the capacity of local people to take joint action to contribute in a consistent way to rural development and to sustainable agriculture. We discuss the assets and limits of local projects based on multi-stakeholder participation to initiate closer links between farmers and other stakeholders and to renew the contribution of agriculture to rural development. Our paper highlights two main points. Firstly, how a social dynamics is initiated and how farmers and other actors take joint action towards sustainable development. Secondly we analyse the impact of such local projects on agriculture and rural development and the counterbalancing effects of global factors, including market trends and related policies. Finally, we discuss the consequences of our results for policies targeting rural sustainable development.