The findings showed that alcohol and tobacco use were reported most frequently in all three surveys, while rates of use of illicit substances were considerably lower. There were decreases in the prevalence of alcohol, tobacco, and stimulant use between 1983 and 1986 and between 1986 and 1989 for both males and females. While the use of inhalants, sedatives, hallucinogens, and narcotics declined between 1983 and 1986, it remained unchanged in the second reporting period. Females reported a lower rate of cannabis use between 1983 and 1989. While it is not known what directly contributed to the decrease in student substance use, during the 6-year period of this study the New South Wales Department of Health and Education initiated several specific programs aimed at decreasing alcohol and tobacco use. Non-government organizations sponsored a range of health-related school programs, and there was an increase in anti-drug media campaigns and general health promotion programs. 3 tables, 8 figures, and 21 references