Editors’ introduction to the Special Issue: The Member States and Differentiated Integration in the European Union

Abstract

European integration has never been a ‘uniform’ process, with one set of rules applying equally to all Member States. Instead, from Rome (1958) to Lisbon (2009), the treaties establishing the European Union (EU) and its predecessors have all contained exceptions from common provisions. The literature refers to this phenomenon as differentiated integration (DI). While DI has always been a feature of European integration, the absolute number of exceptions in EU treaties and secondary law has increased over time (Schimmelfennig and Winzen 2020a). The Lisbon Treaty, for example, is considered a milestone for DI (Koller 2012; Brunazzo 2019). As such, the EU has become an increasingly differentiated political system in recent years (Leuffen et al. 2013; Dyson and Sepos 2010). Despite this, there is surprisingly little research about the attitudes of political actors – such as governments – towards DI. Five contributions in this special issue investigate this gap in the literature. Putting a focus on smaller and less studied EU Member States, they develop in-depth case studies of Austria, Finland, Portugal, Romania, and Slovenia. For better comparability, these papers follow a common approach (see below). In addition, the special issue contains a thematic contribution which explores whether the EU’s differentiated Banking Union will ultimately converge in uniform integration or see further differentiation.