This article considers the issue of political and economic divergence which has emerged in Eastern Europe between the Central and Eastern European (CEE) and Baltic countries on one hand and the Western Commonwealth of Independent States (CIS) countries (Belarus, Moldova, Russia, and Ukraine) on the other. Particular attention is devoted to the questions of whether and to what extent European Union (EU) enlargement deepens the divergence and whether developments in the various arenas are mutually reinforcing or mitigating. The key argument is that divergence may be less severe and less permanent than is often assumed.