A questionnaire concerning drug abuse was administered to 19,948 new military inductees over a six-month period. Almost one-third of the subjects had used drugs, but most were casual users. Marijuana and hashish were most frequently used. There were higher rates of use among college dropouts and men from unstable families, urban areas, and families with high incomes. There was little racial difference in overall drug use. However, non-whites used amphetamines, barbiturates, and heroin twice as much as whites, while whites tended to use marijuana, hashish, and hallucinogens.