Thomas Christiansen holds a Chair in European Institutional Politics at Maastricht University, the Netherlands and is Co-Director of the Centre for European Research in Maastricht (CERiM). He is Executive Editor (with Simon Duke) of the Journal of European Integration and has published widely on the politics of the European Union.Diane Fromage is Assistant Professor of European Law at Maastricht University, the Netherlands and Research Coordinator at the Centre for European Research in Maastricht (CERiM). Her research mainly focuses on parliaments in the European Union, fiscal councils and the European Central Bank.