The Monitoring the Future (MTF) study is an ongoing series of national surveys of American adolescents and adults that has provided the nation with a vital window into the important, but largely hidden, problem behaviors of illegal drug use, alcohol use, tobacco use, anabolic steroid use, and psychotherapeutic drug use. For more than a third of a century, MTF has provided a clearer view of the changing topography of these problems among adolescents and adults, a better understanding of the dynamics of factors that drive some of these problems, and a better understanding of some of their consequences. It has also given policymakers and nongovernmental organizations in the field some practical approaches for intervening. This annual monograph series has been the primary vehicle for disseminating MTF's epidemiological findings. This latest two-volume monograph presents the results of the 35th survey of drug use and related attitudes and beliefs among American high school seniors, the 30th such survey of American college students, and the 19th such survey of 8th- and 10th-grade students. Results are also reported for high school graduates followed in a series of panel studies through age 50. Results from the samples of 8th, 10th, and 12th graders are contained in "Volume I", which is preceded by two national press releases and an advance summary report. Results on college students and other adults are reported each year in "Volume II", which is published a few months after "Volume I". Two of the major topics included in this report are (a) the "prevalence and frequency" of drug use among American secondary school students in 8th, 10th, and 12th grades and (b) "historical trends" in use by students in those grades. Distinctions are made among important demographic subgroups in these populations based on gender, college plans, region of the country, population density, parents' education, and race/ethnicity. MTF has demonstrated that key attitudes and beliefs about drug use are important determinants of usage trends; thus, they are also tracked over time, as are students' perceptions of certain relevant aspects of the social environment--in particular, perceived availability, peer norms, use by friends, and exposure to use of the various drugs. Data on grade of first use, usage trends in lower grades, and intensity of use are also measured. Appendices include: (1) Prevalence and Trend Estimates Adjusted for Absentees and Dropouts; (2) Definition of Background and Demographic Subgroups; (3) Estimation of Sampling Errors; (4) Trends by Subgroup: Supplemental Tables for Secondary School Students; (5) Trends in Specific Subclasses of Hallucinogens, Amphetamines, Tranquilizers, Sedatives, and Narcotic Drugs other than Heroin; and (6) Trends in Drug Use for Three Grades Combined. An index is included. (Contains 242 tables, 123 figures, and 129 footnotes.) [For Volume II, see ED514367.]