This book aims at discussing the future steps in the European Integration, which are to be taken after the likely entry into force in 2010 of the Lisbon Treaty. Against the background of the drafting of this new treaty and the constitutional discussion within EU law during the last decades, the author questions whether the treaty and leading EU law theorists have really grasped and addressed the true future challenges of European integration. Instead of always trying to balance supra-nationalism and inter-governmentalism and seeing the EU as less democratic than a nation-state, at least the doctrine, normally more radical than political decision-makers, ought to embrace the most characteristic trait of European integration, namely supra-national decision-making, and discuss its future potential.