The relationship of relative weight and of skinfold thickness to the 5-year incidence (632 cases) of coronary heart disease was examined in men aged 40 through 59 years at entry to the study: 2442 U.S. railroad men; 2439 men in northern Europe; and 6519 men in southern Europe. Disregarding other variables, an excessive incidence of coronary heart disease was associated with overweight and obesity in the U.S. and southern Europe but not in northern Europe. There were 163 cases of death or definite infarction; this incidence was not significantly related to any of the measures of relative weight or obesity in any sample. Multivariate analysis of the data showed that no measure of relative weight or obesity made a significant contribution to future coronary heart disease, when the factors of age, blood pressure, serum cholesterol, and smoking were comparable. Essentially identical results were found with different multivariate methods.