The book is dedicated to the question of how much room for national tax policy Member States of the European Union will find necessary and possible to maintain in the future. It focuses on the possibilities Member States have and the constraints they face, such as the need to enhance competitiveness and attractiveness to inward foreign direct investment, to finance social programmes and the limitations imposed by European and International Law. The research question is looked at from economic as well as from legal points of view. This comprehensive approach and the answers given will be of interest to scholars and policy makers alike and may guide the path for future tax developments in Europe. .