The creation of the European Union arguably ranks among the most extraordinary achievements in modern world politics. Observers disagree, however, about the reasons why European governments have chosen to co- ordinate core economic policies and surrender sovereign perogatives. This text analyzes the history of the region's movement toward economic and political union. Do these unifying steps demonstrate the pre-eminence of national security concerns, the power of federalist ideals, the skill of political entrepreneurs like Jean Monnet and Jacques Delors, or the triumph of technocratic planning? Moravcsik rejects such views. Economic interdependence has been, he maintains, the primary force compelling these democracies to move in this surprising direction. Politicians rationally pursued national economic advantage through the exploitation of asymmetrical interdependence and the manipulation of institutional commitments.