Two cross-sectional surveys were conducted in 1985 and 1986 to measure the prevalence of coronary heart disease (CHD) risk factors in Blacks and Whites. A home interview was followed by a survey center visit. Participation rates were 78 per cent and 90 per cent for the home interview and 65 per cent and 68 per cent for the survey center visit. Adjusted for age and education, systolic and diastolic blood pressure was 3 to 4 mmHg higher in Blacks. Hypertension was more prevalent in Blacks than Whites (44 per cent vs 28 per cent); serum total cholesterol was approximately 0.4 mmol/l lower in Black than White men and 0.08 mmol/l lower in Black than White women. Among men, more Blacks than Whites were current cigarette smokers (44 per cent vs 30 per cent); however, White smokers smoked more cigarettes per day (26 vs 17). Similar differences were noted for women, although the prevalence and quantity of cigarette consumption was less than men. The excess prevalence of these CHD risk factors in Blacks, especially among women, may explain their elevated CHD and stroke mortality rates in the Twin Cities.