Differentiated Integration in the European Union

The notion of Differentiated Integration is increasingly used in the literature on European integration. Often employed interchangeably with the notion of &quote;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.