The proposed enlargement of the European Union to include countries from Central and Eastern Europe has become an important political issue. Widening the European Union focuses on those institutional reforms of the Union that may be necessary to make the enlargement possible. The institutional structure, originally designed for the Union of just six states, might not be suitable for a EU of twenty-seven or more member states. An overview of current rational choice theories of institutional change is provided before the volume focuses on several aspects of institutional reforms in the Union. Widening the European Union contains contributions from a distinguished team of European academics. This book is a valuable resource to students of the European Union with an interest in its politics and policy, enlargement and institutional reform.