The diverse and excellent set of authors assembled in this book sheds light on the continuing and conflicting calls for deregulation and re-regulation of important industries and informs the ongoing, increasingly global, policy debate over the evolving line between regulation and general competition policy. The purpose of this book is to understand the debate and its policy implications, focusing on the traditionally regulated sectors of telecommunications and energy, and comparing approaches in the European Union and the United States. The book also contains contributions that generalize across industries, thus lending relevance beyond the two sectors that anchor the book.Innovatively combining legal and economic views, Antitrust and Regulation in the EU and US will be of great interest to scholars of competition law, international law firms, and competition authorities and sector-specific regulation authorities (federal and state).