Competition laws have only applied to many participants in the health care industry in Australia and New Zealand since the mid 1990s. Since then, the Australian Competition and Consumer Commission has considered a number of applications by medical practitioner associations and private hospitals to authorise potentially anti-competitive conduct, while the New Zealand Commerce Commission has successfully prosecuted a group of ophthalmologists. Amongst medical practitioners, however, there is still confusion and misunderstanding concerning the type of conduct caught by the Australian Trade Practices Act 1974 (Cth) and the New Zealand Commerce Act 1986 (NZ). This is of serious concern given the substantial penalties associated with price-fixing and restrictive trade practices. This article examines the provisions of these Acts most relevant to medical practitioners as well as a number of determinations and judicial decisions. To provide practical assistance to medical practitioners, the key lessons are extracted.