1. The relation between plasma high-density lipoprotein (HDL) cholesterol concentration and multiple coronary-risk factor status has been assessed in fifty-two middle-aged clinically healthy men from urban and rural Jamaica. 2. Rural hill-farmers had a superior exercise performance (assessed by the responses to submaximal test exercise), less body fat, and lower fasting levels for plasma total cholesterol, low-density liproprotein (LDL) cholesterol, total triglyceride and blood glucose than urban businessmen. Mean plasma HDL cholesterol was considerably higher in farmers then businessmen. 3. Multilinear regression analysis showed HDL cholesterol concentration to be independently and inversely correlated with plasma triglyceride, LDL cholesterol and diastolic blood pressure and that these relationships applied across the urban and rural sub-groups. There was also some evidence that HDL cholesterol concentration increased with stature. When these factors were taken into account, age, ethnic group, adiposity, weight, exercise performance, smoking history and blood glucose made no further significant contribution to the prediction of HDL cholesterol concentration. 4. Thus plasma HDL cholesterol concentration was highest in those subjects with the lowest coronary-risk as predicted by their multiple risk-factor status, an observation which supported other evidence that coronary-risk is inversely related to plasma HDL concentration. 5. The results raise the possibility that coronary-risk can be more simply estimated from the plasma HDL cholesterol concentration than from a consideration of other major lipid risk factors and blood pressure.