In 1963 a sample of 973 men, all 50 years old, was drawn from the population register of Gothenburg, Sweden. These men have been followed up for 17 years with repeated examinations regarding a number of variables possibly related to cardiovascular disease. The latest examination, at the age of 67 years, focused on congestive heart failure (CHF). The incidence rate of manifest CHF varied from 1.5 to 10.2 cases (1000 population)-1 yr-1, depending on which age group was being studied. For the age group 50-67 years the incidence of manifest CHF was 5.5 (1000)-1 yr-1. A large number of factors associated with the risk of acquiring CHF were identified. In multivariate regression analyses, hypertension and smoking were the major independent risk factors. Body weight, heart volume, T-wave abnormalities, heart rate variability, peak expiratory flow rate, psychological stress and Fy-antigen (a genetic marker?) were also independent risk factors. Possible strategies for prevention are discussed.