This book offers a comprehensive analysis of the creation, structure, and impact of the European External Action Service (EEAS)—the EU’s diplomatic service established by the Lisbon Treaty in 2009 and operational since 2011. The EEAS was conceived to make EU foreign policy more coherent and effective by merging staff from the European Commission, the Council Secretariat, and national diplomatic services into a single body under the leadership of the High Representative for Foreign Affairs and Security Policy. The book explores the political and bureaucratic negotiations that shaped the EEAS, the institutional tensions between supranational and intergovernmental actors, and the challenges of forging a unified European diplomatic identity in a post-Westphalian international order.

Chapters investigate the EEAS’s relationships with other EU institutions and member states, its evolving diplomatic practices, and its efforts to promote EU interests and values globally. The volume draws on a range of theoretical perspectives—including bureaucratic politics, historical institutionalism, and organizational theory—to assess whether the EEAS has transformed European diplomacy or remains constrained by national interests and institutional fragmentation. The book also addresses the practical challenges faced by the EEAS, such as maintaining continuity in foreign policy, balancing member state sovereignty, and increasing the EU’s influence on the global stage.

By analyzing the EEAS’s first decade, the contributors provide critical insights into its successes, shortcomings, and future prospects as a diplomatic actor. The book is essential reading for scholars and practitioners interested in European foreign policy, diplomacy, and the ongoing evolution of international relations beyond the Westphalian state system.