…the book combines a thorough (systems) theoretical understanding of constitutional law and world society with a detailed analysis of its implications for concrete cases in this highly complex field. The author deals with a rich pool of theoretical scholarship, including Niklas Luhmann, Gunther Teubner, Hans Kelsen, Martti Koskenniemi, and Anne-Marie Slaughter; but even more importantly for the reader, he also draws on a rich pool of examples of transconstitutional problems. Thus, the book gives a new impulse to the ongoing debate on global constitutional law. It helps practitioners, especially constitutional judges, to comprehend the social conflicts that (invisibly) determine their decisions. For scholars, the book provides an example of the operationalization of system theory to address normative problems in a multicentric world.