Owen Parker is Senior Lecturer in European Politics at the University of Sheffield. Before moving to Sheffield in 2012 he was a Research Fellow at the University of Warwick. Prior to that, he worked for the European Commission in Brussels, Directorate General for Enlargement, on Turkey's bid for EU membership (2003-6). He has published on a range of themes related to the EU, including theories of governance, political economy, Brexit and migration. His current, more narrowly focused, research and policy work focuses on the challenges encountered by marginalised EU citizens in the post-Brexit United Kingdom.Simon Bulmer is Emeritus Professor of European Politics at the University of Sheffield. Having held lectureships at Heriot-Watt University and the University of Manchester Institute of Science and Technology (UMIST), he moved to the University of Manchester in 1989, and was Professor of Government from 1995. He has held a Jean Monnet ad personam chair since 1999 and has been an Academician of the Social Sciences since 2001. He retired from Sheffield in summer 2020. He has been a Visiting Professor at the College of Europe Bruges, the Autonomous University of Barcelona, the Stiftung Wissenschaft und Politik (the German Institute for International and Security Affairs), Berlin, and at LUISS Guido Carli University, in Rome.Charlotte Burns is Professor of Politics at the University of Sheffield. She has taught at the Universities of Aberystwyth, Leeds, and York on EU and European politics and policy, and environmental politics and policy. Before entering academia, she worked in the European Parliament in Brussels for the Chair of the Environment Committee. She has published widely on EU decision making, the powers and the environmental behaviour of the European Parliament, and the impact of the economic crisis upon European environmental policy. She has recently worked on the impact of Brexit upon UK and EU environmental policy.