The paper begins with a brief illustration of the problems related to the protection of rights and constitutionalism in the context of European integration. The present-day challenges to European constitutionalism and the protection of rights through an analysis of the sources of law, the concepts of Constitution and sovereignty are then examined. The paper then points out the circularity that exists between State and Community legal systems and the dualism between the various bodies of guarantee. Finally it underlines how fundamental rights and the protection of those rights should operate as an element of intersection and consolidation between the two levels: in particular, on one hand, as a guarantee of harmonisation of the Community's social tissue and, on the other, as a guarantee for the different identities that exist therein
