Catherine E. de Vries is a professor of European politics, the director of the Oxford Q-Step Centre, fellow in politics at Lincoln College and associate member of Nuffield College at the University of Oxford. In her research and teaching, she focuses on public opinion, political parties, political behavior and European integration. Bernard Steunenberg is professor of public administration and Jean Monnet Ad Personam Chair in European Politics at Leiden University. In his research and teaching, he focuses on analytical politics, decision-making and policy implementation in the EU.