Differentiation in the European Union and beyond

Abstract

This forum article analyzes differentiation among states in the European Union and among regions within states as a single phenomenon, an arrangement in which one or more constituent units opt out of a common policy. By examining differentiation in a variety of contexts, we seek to shed light on its basic features.

Differentiated integration in the European Union: Institutional effects, public opinion, and alternative flexibility arrangements

“…At the end of the day, only if the medium-and long-term benefits and costs on various dimensions of the EU's multilevel system of governance can be estimated, serious evaluations of DI are possible. In addition, the study of DI and its consequences in European governance would benefit from systematic comparison with differentiation in national states (Hooghe and Marks, 2023).…”

“…What makes the EU's "system of differentiated integration" (Schimmelfennig et al, 2015) remarkable, is that it combines vertical differentiation with horizontal differentiation. As Hooghe and Marks (2023) remind us, differentiation is by no means unique to the EU. Yet, it combines vertical and horizontal differentiation to an extent that is atypical even for asymmetrical federal states (on asymmetrical federalism, see, e.g.…”

“…They are particularly relevant in Eurosceptic countries where (exclusive) national identities are strong. As Hooghe and Marks (2023) put it, constitutional DI is a "strategy to lower the temperature of self-determination". As status quo-oriented states, Eurosceptic countries enjoy a favorable institutional bargaining situation in negotiations about deepening.…”

“…Academic work has accompanied the growth of DI, but it initially remained predominantly conceptual and prescriptive, suggesting and categorizing alternative ways in which the EU could develop away from the model of uniform integration (see Holzinger and Schimmelfennig, 2012 for an overview). By contrast, the major general theories of European integration did not pay systematic attention to differentiation, and theory-guided empirical work was extremely rare—Kölliker's (2001, 2006) application of collective goods theory to DI being the main exception.…”

Differentiated cooperation as the mode of governance in EU foreign policy

“…In the recent years studies on differentiated European integration, including in the domain of EU foreign policy, have been flourishing (Héritier, 2021;Hooghe & Marks, 2022;Leruth et al, 2022;Schimmelfennig et al, 2022;Schimmelfennig & Winzen, 2020). Scholarly attention has laid primarily on differentiation in policies where this phenomenon is made evident by differentiated membership, such as in the Euro area or the Schengen zone Matthijs et al, 2019).…”