© Federico Fabbrini 2017. This chapter introduces the book by mapping out the key issues, including the background and the events leading up to the referendum vote on June 23, 2016, which are then examined in depth in the remaining chapters. Specifically, it sets the context of the June 2016 Brexit referendum, analyzes the follow-up to the referendum and the ensuing litigation, discusses the UK notification of withdrawal in March 2017, and examines the start of the negotiations between the UK and the EU in June 2017 and its uncertainties. In addition, the chapter explains the book’s structure and outlines the content of the other chapters of this volume.