Abundant anecdotal evidence is in accord with rigorous research results confirming the existence of various forms of international tax planning by multinational firms. Increasing availability of administrative data for research purposes has enabled researchers to study not only behavioural responses of US-based firms to taxation, but also of European and other multinationals. The present paper summarizes what we can learn from recent studies on tax avoidance strategies by multinational firms in general and by German multinationals in particular. (authors' abstract) / Series: WU International Taxation Research Paper Series