The authors conducted blood pressure screening on the Navajo Indian reservation in northeastern Arizona and northwestern New Mexico. Six hundred forty Navajos over 19 years of age were surveyed at various sites. The mean systolic and diastolic blood pressures in Navajo men and women did not show as great increases with age as those seen among white and black Americans. Navajos also had generally lower blood pressures and lower prevalence of hypertension than white and black Americans. The authors were unable to demonstrate any association between degree of acculturation and blood pressure, but they did find that obesity in both men and women and alcohol use in men were associated with a higher prevalence of elevated pressure in the Navajos.