Assessing the consequences of Brexit on EU policies, institutions and members, this book discusses the significance of differentiation for the future of European integration. This book theoretically examines differentiated integration and disintegration, focuses on how this process affects key policy areas, norms and institutions of the EU, and analyses how the process of Brexit is perceived by and impacts on third countries as well as other organizations of regional integration in a comparative perspective. This edited book brings together both leading and emerging scholars to integrate the process of Brexit into a broader analysis of the evolution, establishment and impact of the EU as a system of differentiation. This book will be of key interest to scholar and students of European Union politics, European integration, Brexit, and more broadly to Public Administration, Law, Economics, Finance, Philosophy, History and International Relations.

Differentiation is becoming an increasingly salient feature of European integration. The multifaceted European crisis and the subsequent Brexit vote (paving the way for a ground-breaking case of differentiated disintegration) have led scholars and practitioners to think about the consequences of differentiated integration. This article draws on five empirical models of differentiation experienced by countries both inside and outside the EU: the European economic area model, the Danish model of (quasi-)permanent differentiation, the Swedish model of de facto differentiation, the instrumental model and the Brexit process of differentiation. It addresses the different risks and opportunities that each of these models entail. The article also introduces the contributions to this symposium, which aims at paving the way for future research on the consequences of differentiation in light of Brexit. This article is part of the 2019 Symposium titled 'Responding to Brexit: Differentiated integration and disintegration in the European Union', which also includes On the Methodology of Studying Differentiated (Dis)integration: Or How the Potential Outcome Framework Can Contribute to Evaluating the Costs and Benefits of Opting In or Out by Marian Burk and Dirk Leuffen (), The End of Exceptionalism and a Strengthening of Coherence? Law and Legal Integration in the EU Post-Brexit by Paul James Cardwell (), Differentiated (Dis)integration in Practice: The Diplomacy of Brexit and the Low Politics of High Politics by Øyvind Svendsen and Rebecca Adler-Nissen () and Rethinking Britain's Role in a Differentiated Europe after Brexit: A Comparative Regionalism Perspective by Philomena Murray and Alex Brianson ().

Differentiated integration has become a durable feature of the European Union and is a major alternative for its future development and reform. This book provides a comprehensive conceptual, theoretical, and empirical analysis of differentiation in European integration. It explains differentiation in EU treaties and legislation in general and offers specific accounts of differentiation in the recent enlargements of the EU, the Eurozone crisis, the Brexit negotiations, and the integration of non-member states. Ever Looser Union? introduces differentiated integration as a legal instrument that European governments use regularly to overcome integration deadlock in EU treaty negotiations and legislation. Differentiated integration follows two main logics. Instrumental differentiation adjusts integration to the heterogeneity of economic preferences and capacities, particularly in the context of enlargement. By contrast, constitutional differentiation accommodates concerns about national self-determination. Whereas instrumental differentiation mainly affects poorer (new) member states, constitutional differentiation offers wealthier and nationally oriented member states opt-outs from the integration of core state powers. The book shows that differentiated integration has facilitated the integration of new policies, new members, and even non-members. It has been mainly 'multi-speed' and inclusive. Most differentiations end after a few years and do not discriminate against member states permanently. Yet differentiation is less suitable for reforming established policies, managing disintegration and fostering solidarity, and the path-dependency of core state power integration may lead to permanent divides in the Union.

Far from displaying a uniform pattern of integration, the European Union varies significantly across policy areas, institutional development and individual countries. Why do some policies such as the Single Market attract non-EU member states, while some member states choose to opt out of other EU policies? In answering these questions, this innovative new text provides a state-of-the-art introduction to the study of European integration. The authors introduce the most important theories of European integration and apply these to the trajectories of key EU policy areas – including the single market, monetary policy, foreign and security policy, and justice and home affairs. Arguing that no single theory offers a completely convincing explanation of integration and differentiation in the EU, the authors put forward a new analytical perspective for describing and explaining the institutions and policies of the EU and their development over time. Written by a team of prominent scholars in the field, this thought-provoking book provides a new synthesis of integration theory and an original way of thinking about what the EU is and how it works.

In the aftermath of the British referendum to leave the European Union and the European Commission's 'White Paper on the Future of Europe', it is not only time to take stock of the existing literature on differentiated integration, but also to rethink the perimeters of disintegration. We argue that phenomena such as Brexit embrace forms of differentiation which trigger the need for conceptualizing differentiated disintegration altogether. This article first sketches the path of the scholarly debate in a chronological way to grasp the breadth of existing literature. Second, it discusses differentiated disintegration as a potentially new area for research. Mapping several scenarios for future research, we propose that differentiated (dis)integration needs to be conceived as a negotiated, but profoundly path-dependent process, which is structurally locked-in, and deeply conditioned by pre-existing organizations and institutions of European integration.

The Routledge Handbook of Differentiation in the European Union offers an essential collection of groundbreaking chapters reflecting on the causes and consequences of this complex phenomenon. With contributions from key experts in this subfield of European Studies, it will become a key volume used for those interested in learning the nuts and bolts of differentiation as a mechanism of (dis)integration in the European Union, especially in the light of Brexit. Organised around five key themes, it offers an authoritative "encyclopaedia" of differentiation and addresses questions such as: How can one define differentiation in the European Union in the light of the most recent events? Does differentiation create more challenges or opportunities for the European Union? Is Europe moving away from an "ever closer Union" and heading towards an "ever more differentiated Union", especially as leading political figures across Europe favour the use of differentiation to reconcile divergences between member states? This handbook is essential reading and an authoritative reference for scholars, students, researchers and practitioners involved in, and actively concerned about, research in the study of European integration. As European differentiation is multifaceted and involves a wide range of actors and policies, it will be of further interest to those working on countries and/or in policy areas where differentiation is an increasingly relevant feature. The Introduction and chapters 13, 21, 30, and 35 of this book is available for free in PDF format as Open Access from the individual product page at www.routledge.com. It has been made available under a Creative Commons Attribution-Non Commercial-No Derivatives 4.0 license.

Differentiated integration has become a durable feature of the European Union and is a major alternative for its future development and reform. This book provides a comprehensive conceptual, theoretical, and empirical analysis of differentiation in European integration. It explains differentiation in EU treaties and legislation in general and offers specific accounts of differentiation in the recent enlargements of the EU, the Eurozone crisis, the Brexit negotiations, and the integration of non-member states. Ever Looser Union? introduces differentiated integration as a legal instrument that European governments use regularly to overcome integration deadlock in EU treaty negotiations and legislation. Differentiated integration follows two main logics. Instrumental differentiation adjusts integration to the heterogeneity of economic preferences and capacities, particularly in the context of enlargement. By contrast, constitutional differentiation accommodates concerns about national self-determination. Whereas instrumental differentiation mainly affects poorer (new) member states, constitutional differentiation offers wealthier and nationally oriented member states opt-outs from the integration of core state powers. The book shows that differentiated integration has facilitated the integration of new policies, new members, and even non-members. It has been mainly 'multi-speed' and inclusive. Most differentiations end after a few years and do not discriminate against member states permanently. Yet differentiation is less suitable for reforming established policies, managing disintegration and fostering solidarity, and the path-dependency of core state power integration may lead to permanent divides in the Union.