Although the Washington State household survey provided several measures of substance use and abuse, this study focused on three indicators: past 30-day illicit drug use; past 18-month alcohol-use disorder; and past 18-month substance use disorder. Independent variables were White, Black, Asian, and American Indian; poverty status; rural residence; education; marital status; employment; emotional health; stress; friends' drug use; and parents' drug use. The findings show that American Indians in Washington State reported the highest rates of lifetime use of all substances, with the exception of "other opiate" drugs. Particularly notable was the fact that 48.6 percent of American Indians reported lifetime use of marijuana. American Indians also reported the highest lifetime prevalence for alcohol use. These findings can be at least partially explained by the disadvantaged situations of American Indians, particularly regarding socio-demographic and individual risk/protective factors. American Indians began the use of virtually all psychoactive substances at earlier ages than those from other racial/ethnic groups; perhaps this demonstrates the cultural acceptability of psychoactive substance use in some American Indian communities. 8 tables, 10 notes, and 48 references