The purpose of this paper is to provide a systematic explanation of the use of traditional medicine among the native American population living in the San Francisco Bay area. Several hypotheses concerning the factors associated with this behavior are tested. These include tribal grouping, socioeconomic and sociocultural factors, as well as the relationship between traditional medicine and modem Anglo medicine. The analysis is based on a probability sample of 277 native American families, systematically drawn from a specially prepared list of 5,000 in three Bay area counties with the largest native American population (Alameda, San Francisco, and Santa Clara). Traditional medicine was used by almost one out of three families in the sample and it is shown that use of traditional medicine, although related to sociocultural factors, did not detract from the use of modern Anglo medicine.