Surveys of Aleuts on St. Paul Island, Alaska, in 1966 and 1976 found a prevalence of hypertension as high as any reported in the United States. The rate remained high over the 10-year period. Preliminary data from other Aleut villages on the Aleutian Chain indicate that a high prevalence of hypertension may be widespread in this region. Etiologically genetic factors, obesity, and a high salt intake are all present. In addition, an exceedingly high level of cadmium content was found in seal livers, a dietary staple. Isolated locations such as St. Paul provide natural laboratories for possibly elucidating the complex etiology of this disease.