The aim of the International Opioid Overdose Symposium was to review trends in illicit opioid overdose deaths in a number of countries in order to identify strategies for preventing such deaths. Australia was prompted to host this meeting because it has experienced a sustained increase in illicit opioid overdose deaths over the past decade. One response to this increase has been an expansion in methadone maintenance treatment places. An apparent increase in methadone-related deaths among persons in treatment and from diverted methadone has produced community concern about the methadone program. It therefore was timely to meet to discuss trends in heroin and methadone-related deaths in Australia and to invite international speakers to help place recent Australian experience in an international context. A Symposium was jointly convened by the Central Sydney Area Drug and Alcohol Services and the National Drug and Alcohol Research Centre in its role as a WHO Collaborating Centre in the Treatment and Prevention of Drug and Alcohol. Funding for the meeting was provided by the Commonwealth Department of Health and Family Services and the Drug and Alcohol Directorate of the New South Wales Department of Health. This paper summarises the issues discussed at the Symposium.