The present draft of the European Constitution, grants states the right to secession. This is an unusual constitutional clause alien to traditional Continental European constitutional thought, and certainly after 1865 also impossible under American constitutional law. For this reason, it is likely that constitutional lawyers will interpret article 59 narrowly, and in so doing jeopardize its effectiveness. Its main importance lies in containing centripetal tendencies in future European development, i.e. containing the tendency for Brussels to assume an ever-increasing number of competencies. This volume should not only be of importance during public discourse about the adoption of the European Constitution. It should be on the bookshelf of every constitutional lawyer who has to deal with article 59 of the European Constitution.