This timely book addresses the contemporary complexities within competition law, questioning whether the founding principles of competition law still hold true today. It explores three main present-day challenges for competition law: the impact of the digital economy and innovative sectors, the challenges facing emerging countries, and current institutional issues.Written in a clear and concise way, with an emphasis on current trends and practices, this book explores recurring key questions such as what are the impacts of the economic characteristics of a market on legal assumptions and the limits of antitrust. Chapters address topics such as merger control regimes, the creation of specialised competition tribunals, and competition clauses in trade agreements. Challenges to Assumptions in Competition Law takes a fresh look at these important issues for competition law in the digital age, incorporating insights from China, Latin America, Europe and the US. This insightful book will be a useful resource for academics and researchers in competition and commercial law, whilst also providing an informative foundation for lawyers and economists working in the field.