This article addresses the process of growing integration of environmental concerns (referred to as “ecologisation”) in European agricultural policies, and suggests a framework for assessing its effects on agri-food systems: marginal adaptation of the industrial model or ecologically based redesign of production? Following the paths of agro-environmental schemes from the debates within agricultural sciences to their implementation on theround in France and Switzerland enables to point out various scientific, political and social features for introducing nature conservation plans within production systems. The impacts and limits of ecologisation are assessed by using the contrasted conceptual frameworks of the Ecological Modernisation and Treadmill of Production theories. We conclude putting the emphasis on the need to carefully take in account the relations between the different spatial scales involved in this evaluation, from the local one to the international one