In October 2022, the Academy of European Law (ERA) in Trier celebrated its 30th anniversary with a congress devoted to the legal dimension of the European sovereignty. 1992 was not only the year in which the ERA was founded, but also a key moment in the history of European integration, as it marked the signing of the founding treaty of the European Union, the Treaty of Maastricht. While sovereignty was a highly controversial issue at the time, the (geo)political and economic challenges facing the Union in recent years have brought it back to the centre of the debate. This book brings together some of the papers presented at the Jubilee Congress and explores recent concepts such as 'budgetary sovereignty', 'strategic sovereignty', and 'digital sovereignty'.