This report is the seventh in an annual series reporting the drug use and related attitudes of America’s high school seniors; the findings come from an ongoing national research and reporting program, “Monitoring the Future: A Continuing Study of Lifestyles and Values of Youth,” also known as the High School Senior Survey. Data on two major topics are reported: current prevalence of drug use among high school seniors (especially illicit drug use), and trends in use since 1975. Also reported are data on grade of first use, trends in use at earlier grade levels, intensity of drug use, seniors’ attitudes and beliefs concerning various types of drug use, and their perceptions of certain relevant aspects of the social environment. Eleven separate classes of drugs are distinguished, including marijuana, inhalents, hallucinogens, cocaine, heroin, natural and synthetic opiates other than heroin, stimulants, sedatives, tranquilizers, alcohol, and cigarettes. The report also includes sections dealing with the use of non-prescription stimulants such as diet pills, stay-awake pills, and psuedo-amphetamines, and trends in use at the higher frequency levels gathered from reports of the duration and intensity of the highs experienced by drug type. Numerous tables and figures illustrate the results. (MCF)