In the 1940s I was struck by reports about many apparently healthy middle-aged men who dropped dead instantly from heart attacks. The causes of these sudden deaths were unknown. I was interested to discover physio-chemical characteristics of individuals with predictive value for the occurrence of these fatal heart attacks. The discovery ofpreventive variables would point ways to prevent this disease. In order to find relationships between mode of life and susceptibility to heart disease contrasting populations had to be studied. Variety - not a high degree of homogeneity in culture and habits - must be sought. After exploratory surveys in countries with supposed differences in dietary patterns, lifestyle and heart disease rates in the early 1950s, the Seven Countries Study took off in 1958. This study established relationships between risk factors and development of heart disease in middle-aged men in health examined in countries with cultures we demonstrated to contrast in diet and lifestyle. The results obtained in the Seven Countries Study from its inception till now are presented in this book entitled: "Prevention ofcoronary heart disease. Diet, lifestyle and risk factors in the Seven Countries Study. " Long ago I realized that our concern should not be restricted to the prevention of coronary heart disease but should be extended to all diseases and premature death.