The present study was undertaken to determine the incidence and related risk factors for coronary heart diseases and hypertension in the rural population of Kheda district, Gujarat (India). The observations from the first five years of this ongoing project (May 1987-May 1992) are described in this paper. Out of an initial sample of 750 individuals in the age group 30-62 years, who were selected by stratified random sampling, 714 persons (males = 429; females = 285) were actually studied, after excluding those suffering from coronary heart diseases (CHD). Initially, all the included subjects were examined clinically and appropriate laboratory investigations were done. A detailed socio-economic history was also obtained. Subsequently all of them were followed up and biannual clinical and laboratory investigations were performed. Cases of CHD were diagnosed according to the recommendations of the New York Heart Association. The overall five-year incidence of CHD was 25.17 per thousand persons. The incidence in males was 3 times higher than in females. More males suffered from myocardial infarction (MI), while in the females the incidence of sudden death was higher (33.3%). The average yearly mortality rate due to CHD was 2.46 per thousand persons. CHD was significantly associated with increased blood pressure (both diastolic and systolic), smoking, and family history of heart disease, and was weakly associated with body weight (p = 0.06).