Economic integration in general and Eastern enlargement of the European Union in particular created a wider European single market, thereby stimulating structural adjustment and economic specialization. This study analyzes trade specialization patterns in the enlarged European Union with a special focus on the new EU member states and the cohesion countries. From a sectoral trade point of view, empirical findings on revealed comparative advantage and a broader picture of competitiveness on the single market are presented. Furthermore, we analyze whether trade specialization patterns converge within the enlarged EU. Empirically identifying the determinants of successful trade specialization and taking into account the role of foreign direct investment, we offer new insights into the dynamics of trade, innovation and integration. Finally, policy options for the new EU member states are evaluated. Thus this work increases our understanding of the nature of international adjustment processes.