The functionalist perspective on the law relating to international organizations is being replaced by a constitutionalist perspective in light of the need to control international bureaucracies engaging in quasi-sovereign activities or violating rules of international law. For this book, editors Klabbers and Wallendahl (Center of Excellence in Global Governance Research, U. of Helsinki, Finland) bring together contributors from European countries to explore this paradigm shift and how it affects the various doctrinal issues that make up the law of international organizations. A section on general issues addresses topics such as membership and financing in international organizations, dispute settlement, and the role of the International Law Commission. A section on special issues examines areas such as ultra vires doctrine and deformalization of international organization law. Chapters on the EU and the United Nations examine the facets of constitutionalism in international organizations