This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book examines the evolution and key characteristics of European Union (EU) governance from the perspective of the myriad political challenges facing the integration project. It also examines the legal challenges of the European Union in the post-Lisbon era. The book discusses the effect of the Economic and Monetary Unions (EMU's) institutional design on its operation, with special emphasis on economic governance in the EMU and its evolution. It offers a critical view on the persistence of the financial turmoil in the EU. The book engages in the contemporary political and scholarly debate on social dissatisfaction and the corresponding political backlash. It deals with the sword of Damocles of various Member State dropout scenarios – such as Brexit, Grexit and others – that is hanging over the EU.