Highlights from the survey include: in 1990, persons aged 26-34 had the highest rate of ever having used drugs (62.6 percent), followed by persons aged 18-25 (55.8 percent) and those aged 35 and older (25.9 percent); in all age groups, males had higher rates of ever having used drugs than females, 42.2 percent compared to 32.1 percent; for individuals aged 26-34, Whites had the highest rate of ever having used drugs (67.6 percent), followed by Blacks (53.7 percent) and Hispanics (45 percent); and for all age groups, White females had higher rates of ever having used drugs (34.3 percent), compared to Hispanic females (24.8 percent) and Black females (27.2 percent). This report presents population estimates of drug abuse for 1990. Data for this report were obtained from the National Household Survey on Drug Abuse. The data was collected through surveys conducted from March 12, 1990, through June 30, 1990 with 9,259 individuals from the household population. Age and race/ethnicity were the two primary correlates of drug use for stratifying the sample of households. The tables contain prevalence estimates for specific drugs and drug classes and are presented by sex, age, race/ethnicity, and region. The specific drugs covered in this report include marijuana, cocaine, crack, inhalants, hallucinogens, any psychotherapeutics, stimulants, sedatives, tranquilizers, analgesics, alcohol, cigarettes, smokeless tobacco, PCP, and heroin. Tables