This study examined the relationship of Minnesota Multiphasic Personality Inventory (MMPI) measures, including the MacAndrew alcoholism (MAC) scale, and the Sensation Seeking Scales (SSS) to adolescents' drug use across nine drug categories. Subjects were 51 male and 72 female high school students between the ages of 14 and 18 (mean age = 16 years, 5 months). The drug use/abuse measure consisted of adolescents' self-reports on the Segal (1973) Alcohol-Drug Use Research Survey. Drug categories included for investigation were alcohol, amphetamines, barbiturates, caffeine, cocaine, hallucinogens, marijuana, narcotics, and tobacco. Scores from standard MMPI scales, the MAC scale, and the SSS were examined in relation to individual drug use outcomes, and multivariate procedures were used to predict polydrug versus single drug use patterns. Results demonstrated significant and meaningful relationships between personality measures and drug use among adolescents, with consistently strong findings for the SSS.