The European Union has flourished and expanded over the last fifty years as a unique system that lies midway between a federal state and an anarchical international system. Different actors coexist within a cooperative hegemony of Member States, and the allocation of competences and decision-making among them has always been at the centre of the integration process. In fact, demands for clearer limits to the Unionand’s decision-making power and enduring tension over the nature and purpose of European integration have been the key drivers of integration and change. This deeply informed and thoughtful book thoroughly examines the manner in which the principle of division of powers has developed in EU Law over the course of European integration, and casts light on the path towards a more efficient delimitation of internal competence between the main actors: namely, the European Union and the Member States. Among the topics investigated in depth are the following: the place of the and‘competence provisionsand’ in the current and future EU Treaty structure; the scope and limits of the powers of institutional actors involved in EU decision-making; the contribution of the Court of Justice in declaring the pre-emptive effect and overarching precedence of Community law; the role of subsidiarity as a tool for monitoring the jurisdictional limits of the Communityand’s legislative competence; areas where and‘creeping competenceand’ occurs; the constitutional checks and balances available to Member States against unprecedented expansion of EU competences; and the spectre of a powerful and‘coreand’ Europe and a and‘multi-speedand’ Europe of pacesetters and laggards. Addressing numerous crucial issues and– among them the degree of permanence of the nation-state in a context of ambiguous constitutional authority, and the width of the democratic base of the Unionand’s and‘institutional dynamicand’ of cooperation and consensus and– the author lucidly describes a seeming paradox: an and‘ever-closer unionand’, with a growing democratic legitimacy, congruent with a supranational community that falls short of a fully-fledged democratic political entity. The countless perspectives and clarifications discovered along the way are sure to engage academics and policymakers working in the fields of the European integration project, and will provide ample insights and food for thought.