If farmers are to meet the new challenges facing agriculture (environment, rural development, etc.), appropriate knowledge has to be produced. But observations in six EU countries (France, Germany, Greece, the Netherlands, Spain and the UK) show that unexpected problems arise when technical support for agriculture is linked to market regulation, as recommended since the late 1980s. The source of these problems can be understood better by applying concepts from the service economy: i) The production of new knowledge requires strong interaction between service providers (technical support bodies) and beneficiaries (farmers). The weakening of non-market regulation procedures, which partly guaranteed these possibilities of interaction, makes the conception of an advisory service difficult. ii) As soon as consultancy becomes a paying service, some beneficiaries reduce technical interaction with their colleagues in order to benefit from a productive advantage, and the ‘multipliable’ nature of new knowledge is reduced. iii) An increasing number of farmers are excluded from the benefits of technical support v though they help to provide services that society expects from agriculture (management of the land, maintenance of activities in low-density areas). iv) The responsibility for combining contradictory requirements (competitiveness, environment, rural development) is most often put on the shoulders of individual farmers who are unequipped to deal with such complex issues. Observed trends attest to the fact that effects often run counter to the stated agricultural and rural development objectives of policies.