The data reveal that overall rates of adolescent drug use increased quickly in the late 1960's and early 1970's to reach epidemic proportions. The epidemic peaked in the late 1970's, after which prevalence rates dropped slowly but steadily for most drugs. Disturbing increases have been noted since 1993 for several drugs, especially marijuana. In addition, the problem has not yet returned to the levels before the epidemic began. Currently, more than half of high school students report some use of an illicit drug before they graduate from high school. Rates of use are higher among youth who do not graduate. In addition, alcohol abuse costs the United States nearly twice as much as illicit drug abuse does, but adults and adolescents generally regard its use as acceptable. Alcohol and tobacco cannot be separated from the illicit drugs without giving youth a mixed message about drug problems. However, the data also suggest that straightforward, factual drug education can reduce drug use and that children need education before they reach the critical period of ages 12-17. Figures, table, notes, and 22 references