post Dissemination of the document: INRA Rural Economy and Sociology Unit 4 Allée Adolphe Bobierre CS 61103 35011 Rennes cedex (FRA) All the countries studied, in particular the EU, Argentina, the United States, Japan and Switzerland, have put in place relatively similar programmes to reduce the negative externalities of agriculture. These programmes deviate from the polluter pays principle and thus result in a transfer of taxpayers to the agricultural sector. In addition, programmes targeting above-ground farming are very complex, implying excessive implementation costs making their control problematic. They turn out to be ineffective. The main difference between countries is the weight given to positive externalities programmes in the EU as well as in Japan and Switzerland. They are based on the recognition of multifunctionality, which implies economies of scope in the joint production of both market and non-market goods. These programmes correspond to a growing societal demand for a quality environment. They can be an effective way of preserving natural resources and producing management.