The characterization of the European Union (EU) as a multi-level system of governance resulted from controversies about the nature of this political system emerging from European integration. In the wake of the treaty reforms during the 1990s, the EU has progressed beyond a confederation of states towards a particular kind of multi-level system. The Union fulfills a great deal of state functions, but to date it has not evolved into a new supranational state. Whereas a state has legislative power and the power to implement its laws in its jurisdiction, most policies of the EU can only be made by joint or coordinated decisions of European and national institutions. Therefore, the EU deviates from the usual structures of a federal state. Whenever it is designated as a multi-level political system sui generis, two particular traits are emphasized: one is its hybrid character resulting from the combination of federal-like structures in the areas of ‘supranational’policy-making and confederal structures in arenas of intergovernmental cooperation. On the other hand, the term multi-level governance indicates the interlocking between the European, the national and the subnational levels. This second aspect led Fritz W. Scharpf to transfer the concept of joint decisionmaking from theories on German federalism to European politics (Scharpf 1988). Later, when the regions arrived on the European scene and the interplay between levels became more complex through the invention of new modes of coordination, the term multi-level governance took hold (Marks et al. 1996; Benz 2000; Hooghe and Marks 2001). This concept now has come to characterize the interdependence among European, national, and subnational policy-making as a general feature of the political system of the EU. This shift in terms has had ambivalent consequences. Without doubt, the concept of multi-level governance is better suited to describe the complex structure of European policy-making than the term joint decision-making, in particular as it covers relations between both territorially and functionally defined units. This holds especially true if not only the European legislation through joined actions of the Council, the European Parliament and the Commission is taken into account but also the preparation of decisions in negotiations between public and private actors from all levels as well as the implementation of European policies. In contrast to terms like federal or confederal, the notion of governance refers to the fact that more often than not private actors are involved in policy-making. Moreover, by applying the analytical concept of multi-level governance, we can better comprehend the real variety of governance than by referring to concepts like ‘condominio,’‘consortio’(Schmitter 1996), the ‘fusion of levels’(Wessels 1997) or ‘network governance’(Kohler-Koch and Eising 1999). Nonetheless, all concepts used to understand the multi-level system of the EU have