This work investigates the mechanisms and political logic driving the expansion of the European Union toward Central and Eastern Europe. Frank Schimmelfennig and Ulrich Sedelmeier analyze the tension between the EU's liberal democratic values and the strategic interests of its member states. By synthesizing constructivist and rationalist institutionalist frameworks, the authors explain why the EU extended membership to post-communist states despite significant economic and political costs. The text provides a rigorous examination of the conditionality policies that shaped the accession process.

Scholars and students of European integration frequently cite this text as a foundational analysis of the enlargement process. Experts highlight the authors' ability to balance complex theoretical arguments with empirical evidence, making it a standard reference for understanding EU institutional expansion.