This collection celebrates the career of Professor Alan Dashwood, a leading member of the generation of British academics who organized, explained, and analyzed what we now call European Union law. The festschrift takes as its starting point Professor Dashwood's vivid description of the EU as a 'constitutional order of states.' He intended that phrase to capture the unique character of the EU. On the one hand, it is a supranational order characterized by its own distinctive institutional dynamics and an unprecedented level of cohesion among, and penetration into, the national legal systems. On the other hand, it remains an organization of derived powers, the Member States retaining their character as sovereign entities under international law. This theme permeates both the constitutional and the substantive law of the EU. Contributors to the collection include members of the judiciary and distinguished practitioners, officials, and academics. They consider the foundations, strengths, implications, and shortcomings of this conceptual framework in various fields of EU law and policy. The book will be essential for anyone interested in the constitutional framework of the contemporary European Union.