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.

The notion of Differentiated Integration is increasingly used in the literature on European integration. Often employed interchangeably with the notion of "flexible integration, diverging views on its nature have led to the emergence of various definitions and, to some extent, a semantic confusion. A lack of consensus characterizes the academic literature; some authors even avoid putting an explicit definition on the term. The main objective of this book is to seek answers for the following questions: How can one define Differentiated Integration in the European Union? Should Differentiated Integration be considered as a process, a concept, a system or a theory? Should it be seen as a temporary or a well-established phenomenon? How is this field of study likely to develop in the future? In order to do so, all chapters, written by leading experts in the field, offer a state-of-the-art analysis of the study of differentiated integration, from theoretical and practical perspectives. In addition, this book is not a collection of isolated papers: all chapters are interconnected and gravitate towards the aforementioned central questions, but approach these from different perspectives. This book was published as a special issue of the Journal of European Public Policy.

Far from displaying a uniform pattern, European integration varies significantly across policy areas and individual countries. Why do some member states choose to opt out of specific EU policies? Why are some policies deeply integrated whereas others remain intergovernmental? In this updated second edition, the authors introduce the most important theoretical approaches to European integration and apply these to the trajectories of key EU policy areas. Arguing that no single theory offers a completely convincing explanation of integration and differentiation in the EU, 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.

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.

The European Union (EU) is often portrayed as sacrificing national diversity for European unity. This book explores the alternative of a flexible EU based on differentiated rather than uniform integration. The authors combine normative theory with empirical research on political party actors to assess the desirability and political acceptability of differentiated integration as a means of accommodating heterogeneity in the EU. They examine the circumstances and institutional design needed for flexibility to promote rather than undermine fairness and democracy within and between member states. Clear, balanced, and accessible, the book provides fresh thinking on the future of the EU.

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.

Differentiation was at first not perceived as a threat to the European project, but rather as a tool to promote further integration. Today, more EU policies than ever are marked by concentric circles of integration and a lack of uniform application. As the EU faces increasingly existential challenges, this timely book considers whether the proliferation of mechanisms of flexibility has contributed to this newly fragile state or whether, to the contrary, differentiation has been fundamental to integration despite the heterogeneity of national interests and priorities.