The eastern enlargement of the European Union is one of the most significant developments in the history of European integration since the end of World War II. This is due to the large number of accession countries and the variety of cultures and structures and the challenges presented by their systems'' transformations. The essays in this collection, planned on the occasion of a symposium on Central and Eastern Europe held at the University of Salzburg, focus on a variety of countries, offer a variety of perspectives, and invite comparisons. This volume includes eleven contributions from fourteen scholars that raise key questions regarding the role of institutions, actor constellations, interests and rational choice, the importance of commonalities, identities or perceptions of welfare, and the influence of basic values and basic norms. Theoretical approaches employed are interest analysis and bargaining concepts, policy analysis, and constructivism. In some contributions, the authors reflect not only on the challenges and intricacies of the negotiations and the transformations, but also on the national interests and protectionist stances of some of the neighboring EU member states - which appear rather atavistic in the light of the declared EU tenets. Contributors also investigate the importance of political versus economic factors and the different motivations of the candidate basic data on each former eastern bloc country, the results of the voting of the European Parliament and of the referenda on EU membership in the accession countries, as well as a geographical map.