EPUB and EPDF available Open Access under CC-BY-NC-ND licence. Written by a leading expert in the field, this book analyses the complex relations between the European Union (EU) as a regional organization and the United Nations (UN) as an international, global governance institution. The book explores how collaboration between the EU and the UN has evolved and how the two entities collaborate both structurally and in day-to-day work. It shows how the EU acts within institutions such as the United Nations General Assembly and how UN agencies, funds and entities, such as UNHRC, UNICEF and UN Women, interact with the EU and its member states. Through its analysis, the book demonstrates how, despite recent criticism, patterns of multilateralism and cooperation between regional and international institutions can be central to stable patterns of rules-based regional and global governance.