After enjoying considerable success among French scholars, the concept of regulation has now become one of the main political arguments for explaining and justifying policy. Paradoxically, the success of regulation owes more to its ambiguity than its suitability to actual policy and political goals. In order to understand the elements comprising the French regulation discourse, it is necessary to examine both its historical roots and the conditions for its diffusion and hegemony. It is also important to distinguish at least two very different domains within which such discourse is applied. The first relates to macroeconomic policy that, for several reasons, faced the most fundamental ideological and practical transformations. The second relates to territorial policy, which is simultaneously confronted with the reform of public intervention and new spaces of European regulation. The focus on French structural policy implementation will highlight France's peculiar way of negotiating between two new norms of regulation: subsidiarity and regionalisation. The story behind these two concepts shows general similarities, but also reveals interesting differences such as the methods employed to legitimize new regulations, their linearity and ruptures, and the degree of coherence of the new dominant discourses. The paper draws some lessons from the French case to assess the new role set for European regulation.