This concise and practical guide to the most important economic techniques and evidence employed in modern merger control draws on the authors' extensive experience in advising on European merger cases. It offers an introduction to the relevant economic concepts and analytical tools, and stand-alone chapters provide an in-depth overview of the theoretical and practical issues related to market definition, unilateral effects, coordinated effects and non-horizontal mergers. Each form of economic evidence and analysis is illustrated with practical examples and an overview of key merger decisions.