This text introduces the reader to the principles and practice of merger control in the EC and the UK. It deals clearly with both of the new regimes, providing a discussion of the policy and the relevant legislation, clarified through an analysis of pertinent cases and decisions. The aim is to provide the non-expert reader with a thorough and accessible introduction to the subject. The book deals first with matters common to both regimes, including relevant economics, and then focuses on the EC and UK systems as separate entities. In each case the text covers qualifying mergers, including principles of territorial jurisdiction, substantive tests, procedures, appeals, and third party rights, as well as the link between the UK and EC regimes. The book is up to date to 31 July 2006. Substantial appendices provide most of the relevant core legislation in one convenient place.