Numerous studies have documented the sharp East-West division of Europe as far as political attitudes, political behavior and the volatility of party systems are concerned (Rohrschneider and Whitefield 2012, Casal Bertoa, 2013). Much less is known about the regional differences concerning the logics of government formation. Building on a new index of party system closure (Casal Bertoa and Enyedi 2014), and using an original dataset comprising almost 1500 cabinets, this paper investigates the stability of the party relations as reflected by the partisan composition of governments in Europe since the middle of the 19th century. The aim of the analysis is to find out whether the stage of the democratic development or the regional-historical background explains better the variation in the degree of stability, and whether the current differences between East and West are due to the differences in the degree of loyalty among the parties to each other or to the variance in the openness of governments to new party actors. Relying on the most recent data the paper will also estimate the impact of the global financial crisis on the patterns of government formation in both Western and Eastern Europe.