Recent years have witnessed a sharp increase in the number of international courts and tribunals (e.g., WTO, NAFTA, ITLOS, ICC, etc.) and greater willingness on the part of states and other international actors to subject themselves to the compulsory jurisdiction of international adjudicative mechanisms. However, because of the uncoordinated nature of these developments, overlaps between the jurisdictional ambits of the different judicial bodies might occur - i.e., the same dispute could fall under the jurisdiction of more than one forum. This raises both theoretical and practical issues of coordinating between the various jurisdictions. The purpose of this book is to explore the implications of jurisdictional competition and to identify standards that may alleviate problems associated with the phenomenon, which arguably threatens the unity of international law. The first part of the book examines the jurisdictional ambits of the principal international courts and tribunals and delineates areas of overlap between their respective jurisdictions. Them follows a discussion of some of the potential systematic and practical problems that arise out of jurisdictional competition (e.g., forum shopping and multiple proceedings) and considers the expediency of mitigating them. It concludes by identifying existing rules of international law, which govern inter-jurisdictional competition, and considering the desirability of introducing additional norms and arrangements.