Since 1970 there has been increasing research interest in the epidemiological study of substance abuse among American Indians and Alaska Natives. A number of sampling and investigative strategies have been used with varying degrees of success. Among the sampling techniques used in research among Indians are community surveys, captive audience surveys, clinical samples, mortality statistics, alcohol/drug-related arrest records, records of conviction for alcohol/drug offenses, and the social indicator method. Procedures and instruments have included review of recorded data collected by institutions and agencies, serologic and breathalyzer tests, interviews, rating scales, questionnaires, collateral informants, psychological autopsy, and signs of alcohol addiction. Results have shown that there is great variation between tribes in the degree of substance abuse. No strong correlations between any of a number of factors tested have clearly illustrated the reason for variations in the substance use between groups of American Indians and Alaska Natives.