This book examines the evidence involved in proving the existence of an antitrust market under the Australian Trade Practices Act 1974. An antitrust market is a complex eco-legal concept. Proof of such a market is a critical issue that must be tackled in assessing whether business conduct is anti-competitive for the purposes of the Act. It is an issue that arises in most jurisdictions in which competition legislation exists, including New Zealand, the United States and the European Community. Proof of Antitrust Markets in Australia is the first comprehensive analysis of the evidentiary dimensions of this important issue. It provides significant practical insights for lawyers, economists, judges, regulators and business people concerning the evidence required to establish antitrust markets to the satisfaction of the courts. The challenges involved in presenting evidence from industry, consumers, statistical studies, and expert witnesses are each explored in detail. The insights conveyed in the book indicate that while the approach taken by Australian courts to the evidence on this issue may be correct in principle, it lacks rigour in practice. The author makes a range of recommendations as to how the approach could be improved. This particular aspect of the book should be of interest to scholars in the field of competition law generally.