The comparison of the external actions of Canadian provinces enables an analysis of the institutional configuration ' in this case federal ' as a significant factor for differentiation in the extent and methods of operating in the international arena. The examination of the double inscription of provinces in a regional integration process, with the ALENA and in future the ZLEA, and in a globalisation movement of exchanges reveals highly contrasting strategies: with the notable exception of Quebec, the priority given to economic exchanges goes hand in hand with a relegation, or even the abandoning of actions of a para-diplomatic nature. Quebec stands out owing to its ambition to transform international action into a fully-fledged foreign policy. This disparity, which is broadening, has to be resituated in a context characterised by a significant evolution in how federalism is perceived: the varying engagement of federated entities in international relations constitutes a good institutional gauge of the current redefinition of federal-provincial relations, a change which does not exclude a tendency towards centralisation.