Patient characteristics, treatment choices, and long-term survival were examined to seek possible explanations for marked differences in the racial distribution among 6594 consecutive patients who underwent arteriography or coronary artery bypass grafting (CABG) from 1970 to 1978. Overall, the percentage of whites undergoing coronary arteriography was 96% compared with 4% of the blacks; only black females showed a secular increase in the relative percentage. Clinical manifestations and predisposing factors for coronary atherosclerosis differed little between the blacks and the whites in this population. Angina, as measured by the Rose Questionnaire, had the same clinical significance in blacks as in whites. Findings indicated that similar covariates of comparable strength appeared to be operative as indices for severity of coronary heart disease in both blacks and whites. On the basis of regression analyses, whites had approximately a three times greater chance of having two or more diseased vessels than did blacks after adjustment for multiple clinical characteristics and risk factors. After adjusting for pertinent variables, whites with three-vessel disease were two and a half times more likely to have CABG than blacks (42.5% vs 16.2%). However, differences in choice of initial therapy for whites and blacks with multiple-vessel disease were significant only in those older than 50 years. Except for older blacks who demonstrated a decreased survival rate when managed surgically, survival rates were similar for blacks and whites. Trends in the evaluation and clinical management of black populations with suspect coronary heart disease should further clarify these preliminary findings.