By the end of the nineties English environmentalists led by the Royal society for the protection of birds succeeded in imposing their own vision of the agricultural policy to, among others, the national public authorities. According to them traditional agricultural policy should be replaced by a policy which rewarded the “environmental services” that farmers produced: insofar as market exist for agricultural and food products state intervention should limit its responsibility to market failures – the provision of “public goods”. Since then and despite limitations due to European regulations, English agricultural policy has complied with this vision. This policy shift provides therefore a good case study for examining how, over the long term, actors get the ownership of a specific social problem (J. Gusfield): that is how they possess the authority to define the problem (what it is, and what might be done about it) and, in so doing, how they control the production of public policy. In this paper I demonstrate that four causal mechanisms have been especially important in such a process: (1) universalizing a vision through the concentration and accumulation of scientific and technical expertise; (2) coalition building through the mobilization of auxiliary agents (nature conservation agency, Treasury civil servants, politicians, media); (3) making a vision official through policy production, so naturalizing its interpretative frameworks; (4) exporting the vision abroad: I argue that domestic conservationists’ success is inseparable of their ability to promote their vision in international and European organizations, enhancing the amount and the value of their capitals. In other words, mechanisms 1, 2 and 3 are specifically efficient because of mechanism 4. This paper is based on a doctoral research. Its rests specifically on documentary analysis (grey, academic and official literatures) and on 50 interviews (30 conducted in England, 20 in Brussels).
