Agriculture has been put in a new position regarding other activities and territorial actors by the emergence of the policy guideline given by the concept of sustainable development. Based on an analysis of litterature and field study cases, our research examined this new position making the following hypothesis : in new local places where decisions are made, the capacity of agriculture to intervene depends on its capacity to hold a position of mediation. We focus in particular on the case of Chambers of Agriculture which play in France a key role in the development of agriculture. We come to the conclusion that it is necessary for Chambers of Agriculture to establish a certain “autonomy” to take on their role of mediation. This paper develops sociological approaches and reflects a close collaboration with agricultural organisations