Coronary heart disease was uncommon among the Navajo in the past, but appears to have increased substantially over the last few decades. The 1991-1992 Navajo Health and Nutrition Survey, which included interviews and examinations of 303 men and 485 women between the ages of 20 and 91 y, is the first population-based examination of coronary heart disease risk factors in this tribe. Coronary heart disease risk characteristics were common, particularly overweight (men, 35%; women, 62%), hypertension (men, 23%; women, 14%) and diabetes mellitus (men, 17%; women, 25%). Among 20- to 39-y-olds, a large proportion of men reported that they currently smoked cigarettes (23%); use of chewing tobacco or snuff was also prevalent among these 20- to 39-y-old men (37%) and women (31%). Although serum concentrations of total cholesterol were fairly comparable to those seen in the general U.S. population, fasting serum triglyceride concentrations were high (median: men, 132 mg/dL; women, 137 mg/dL), and concentrations of HDL cholesterol were low, particularly among women (median: men, 42 mg/dL; women, 44 mg/dL). Body mass index was associated with levels of most risk factors, and, independently of the level of overweight, a truncal pattern of body fat was related to adverse lipid levels among men. A large proportion of men (20%) and women (30%) reported not having participated in physical activity during the preceding month. Lessons learned from past intervention activities among the Navajo, particularly those for diabetes, may be useful in managing these risk factors to reduce the future burden of coronary heart disease.