The EU is one of the most notoriously complex international organisations. It is the only supranational organisation where nation-states agree to share sovereignty in some areas but not in others. At the heart of the EU debate across Europe are two opposing groups: one aims to devolve more sovereignty to the EU, with the aim of creating a European 'super-state' and the other wishes to devolve less, effectively relegating the EU to a mere discussion forum. In this accessible and engaging book, Mark Corner provides an essential introduction to the history and modern workings of the EU. Focusing on key themes in the union's development and the debates surrounding future enlargement, this book answers the key questions related to the EU and provides a 'one-stop shop' for anyone curious about future of Europe.