The EU is a complex political and institutional machine, with distinct procedures, language and codes. Its functioning is based on negotiations among a variety of actors at different levels (local, regional, national, supranational, inter-institutional, intra-institutional, etc.) as well as in informal and non-legislative contexts. For this reason, the EU can be difficult to understand. Negotiation roleplaying simulations can shed light on the genuine dynamics of the system and are thus becoming an essential element in teaching and training on EU matters. This book is an introduction and a guide to the EU decision-making process and its institutional settings, an essential tool for effective negotiators in the European arena, and an instrument for teachers at any level offering a series of suggestions on how to design successful simulation games.