The main goal is to organize an academic workshop to discuss the future institutions and institutional model of the European Union (EU) in the perspective of new enlargements of its member-states. The -three day- workshop should take place in the fall of 2000 at the EUI and gather leading political scientists and economists. The aim is to provide a theoretically sound reassessment of some of the institutional challenges faced by a large EU. An academic complement to the next Inter Governmental Conference. Topics to be discussed include: how to best delegate different policies to different government tiers and EU institutions; setting checks and balances across EU institutions; defining effective and stable decision rules (e.g., in the Council); territorial representation, the electoral system and the party system of the European Parliament; integration of disparate political and economic systems with the EU enlargement.