This article examines the determinants of public opinion on differentiated integration (DI) in the European Union (EU). Specifically, it tests whether citizen attitudes are informed by the national experience of opt‐outs and exclusions from full participation in EU policies. The study...

This report examines the dynamics of differentiated integration. In particular, it studies whether differentiated integration is a path-dependent process, in which earlier differentiation increases the likelihood of additional differentiation in the future. In a set of analyses on the EU’s...

Since the 1990s, European integration has been characterized by a combination of politicization and differentiation. Starting with the Danish referendum on the Maastricht Treaty in 1992, which has led to a series of Danish opt-outs from the Treaty on European Union, domestic politicization has...

This paper reports a descriptive analysis of the historical development and the modes of differentiated integration in the treaties and legislation of the European Union. Whereas the number of differentiations has increased in the course of European integration, it has remained stationary...

We develop a set of theoretical expectations about the utility of social media as a tool for recruiting participants in a civic campaign, and as a medium capable of changing the views and knowledge of those recruited. We test our hypothesized relationships in a randomized field experiment...