In spite of the proliferation of research on cultural differences in international mergers and acquisitions, we lack systematic analyses of the impact of cultural factors on knowledge transfer. In this paper, we argue that both national and organizational cultural differences and cultural integration in the form of cultural convergence and crossvergence affect knowledge transfer in acquisitions. We develop specific hypotheses concerning the nature of these effects, and test our hypotheses with data on international acquisitions carried out by Finnish corporations. The analyses performed show that national cultural differences provide great potential for knowledge transfer in international acquisitions. Furthermore, organizational cultural convergence and crossvergence have a significant positive impact on knowledge transfer. In particular, convergence and crossvergence moderate the impact of national cultural differences on knowledge transfer.