Prof. Dr. Rainer Prokisch studied law at the University of Munich, Germany. After some years in practice in Germany and abroad, he became assistant lecturer for public law and tax law at the chair of Prof. Dr. Klaus Vogel at the University of Munich where he finished his doctoral thesis in 1992. The underlying research was focussed on the issue of the powers of the German Constitutional Court in respect of the provisions of the German financial constitution. After that he became deputy head of the Research Institute for International and Foreign Tax Law and was responsible for the project of a commentary on Double Taxation Treaties in German und English language. During these years he was, inter alia, General Reporter on behalf of the International Fiscal Association and consultant of the OECD, Paris. In 1998, he joined the International Bureau of Fiscal Documentation, Amsterdam, where he was responsible for the department Europe I and later for the International Tax Academy. Since 1 April 2000 he is full time professor for International and European tax law at the University of Maastricht.