In Sweden, coronary heart disease (CHD) mortality increased by 30% among 50-to 54-year-old men and by 20% among 55- to 59-year-old men between 1968 and 1980. Among women there was no change during the same time. Two cohorts of 50-year-old men living in Gothenburg, Sweden, were examined 10 years apart (1963–1973). Levels of the 3 major CHD risk factors, blood pressure, serum cholesterol and smoking habits, were similar in these two cohorts. Men in the latest examined cohort had almost doubled the 7-year incidence of fatal and non-fatal CHD compared to men in the first examined cohort. Obesity was more prevalent among men examined in 1973 and also a significant risk factor for CHD in that cohort. Increased obesity and very slightly increased serum cholesterol levels can, however, only explain part of the increased incidence of CHD. Hypertension is being more effectively treated, the prevalence of smokers has decreased, and treatment of symptomatic CHD is similarly active in Sweden as in many other countries. Thus, several changes largely parallel those taking place in countries with decreasing CHD mortality. In spite of this, CHD mortality is increasing among males in Sweden. Possible reasons for this are discussed.