This book originates from the proceedings of the 10th anniversary conference of the Centre for the Law of EU External Relations (CLEER) in which renowned experts in the field took stock of recent evolutions in the law and practice of the EU’s external relations. In particular, the book addresses the question of how the evolving legal and political framework affects the nature of EU external relations law. The contributions discuss the actions (and reactions) of the EU through external action instruments in a number of substantive areas such as migration, trade, neighbouring policies, security and defence. By shedding light on the most significant developments of the past decade this edited volume attests to the ever-evolving nature of the field of EU External Relations Law. Thus, this book is essential reading for academics, practitioners and policy makers at the EU level interested in the field of EU External Relations Law. Dr. W.Th. Douma is an Independent legal expert at the European Environmental Law Consultancy and EU Legal – Centre for European and International Law, both based in The Netherlands, voluntary researcher at Ghent University in Belgium, and Senior Legal Adviser at the Dutch Ministry of Social Affairs and Employment. Prof. Dr. C. Eckes is Professor of European Law at the University of Amsterdam and director of the Amsterdam Centre for European Law and Governance, The Netherlands. Prof. Dr. P. Van Elsuwege is Professor of European Union Law at Ghent University and co-director of the Ghent European Law Institute, Belgium. Dr. E. Kassoti is Senior researcher in EU and International Law at the Asser Institute and academic co-ordinator of the Centre for the Law of EU External Relations (CLEER), The Netherlands. Prof. Dr. A. Ott is Professor of EU External Relations Law and Jean Monnet professor in EU Law at Maastricht University, The Netherlands. Prof. Dr. R.A. Wessel is Professor of European Law and Head of the European and Economic Law Department at the University of Groningen, The Netherlands.