Despite the large amount of literature analysing the transition and the growing body of literature on the 'coercive' impact of the EU and NATO, the more 'voluntary' dimensions of policy diffusion remain under-researched. In fact, external influences have been quite substantial, and have manifested themselves in various ways, as an examination of the role of the most important international actors shows. Empirical evidence from an analysis of the transformations in the Czech Republic, Hungary, Poland and Slovakia permits the construction of a framework for the study of external influences on post-communist politics across the phases of transition.