In this era of globalisation, different legal systems and structures no longer operate within their own jurisdictions. The effects of decisions, policies and political developments are having an increasingly wide-reaching impact. Nowhere is this more keenly felt than in the sphere of European Union law. This collection of essays contributes to the co-operative search for interpretative and normative grids needed in charting the contemporary legal landscape. Written by leading lawyers and legal philosophers, they examine the effects of law's de-nationalisation by placing European law in the context of transnational law and demonstrate how it forces us to rethink our basic legal concepts and propose an approach to transnational law beyond the dichotomy of national and international law.