This edited collection examines the changing role of the legal profession as experts in the context of European Union policy-making. Drawing on theoretical and empirical research and the idea of law as a social and political practice, this socio-legal work brings together a group of legal scholars and political scientists to investigate how lawyers, through the deployment of their expertise and knowledge, act as experts in matters of EU related policy-making at the national, European and international levels. It provides new theoretical viewpoints and untold stories from legal experts themselves, promotes an evolving definition of what constitutes legal expertise and what shapes legal experts in a time when experts are in equal measure both revered and ignored, and introduces new critical voices in the field of EU socio-legal studies.