Résumé : Since its origins, there have been competing views concerning the nature, scope and objectives of the process of integration and of the European Union. Attitudes towards Europe and European integration, both among political elites and citizens, have been much studied over the last 15 years. But there is no comprehensive analysis of these competing views of Europe at the supranational level.The existence of radically diverging views on the European political system within the EU’s own institutions is problematic at both theoretical and practical levels. Little is known, however, about this phenomenon, its impact on the EU’s agenda and policy-making as well as on constitutional reform. This book aims therefore at investigating the divergence in views about the European Union in order to lend insight into its consequences for the functioning of the EU and its institutions. It will focus on the main EU institutions, i.e. the Council, Commission, Parliament and Court but will also deal with the visions of various European elites on the EU.