In the Seven Countries Study of Cardiovascular Diseases, 16 cohorts of middle-aged men were enrolled in eight nations of seven countries in three continents in the late 1950s and early 1960s for a total of 12 763 individuals. Thirteen cohorts were located in Europe, two in Finland, one in the Netherlands, three in Italy, two in Croatia - former Yugoslavia, three in Serbia - former Yugoslavia, and two in Greece. Another cohort was enrolled in the USA and two cohorts in Japan. Baseline prevalence of coronary heart disease (CHD) was largely different across areas, as well as 10-year incidence of major CHD events and CHD mortality for periods ranging from 25 to 40 years of follow-up. Higher rates were found in Northern Europe, lower rates in Southern Europe and intermediate rates in Eastern Europe, represented by Serbia. Differences across countries were partly explained by different entry mean levels of serum cholesterol, blood pressure, consumption of saturated fatty acids and adherence to traditional dietary patterns. Forty-year trends of CHD mortality were largely explained by early changes in serum cholesterol and blood pressure levels, with large risk increases in Serbia and Greece, and the tendency to declines in Finland and the Netherlands. These trends in Seven Countries' experience are in line with those manifests in official mortality data. An attempt of interpretation is presented pointing to socio-economic evolution in the involved countries, which heavily modifies health and dietary habits and contributes to explaining these differences at population level.