The study of atherosclerosis centered since the first decade of the present century on etiology and pathogenesis. In fact, the studies of the military academy of medicine in St. Petersburg have opened the way of inducing atherosclerosis in animals. Pathogenesis of atheroma has been studied since then in humans and animals naturally prone to the development of the disease and by a variety of dietary and other procedures. The various experimental studies allowed science to evaluate the relative importance of different factors (genetic, dietary, hormonal, pharmacological. mechanical, circulatory, etc.) in atherogenesis. Epidemiological studies as well as biochemical plasma lipid and lipoprotein estimations coupled with light microscopic, histo­ chemical and electron microscopic investigations decreased the gap between observations on the human and experimental animal research. The enormous literature covering this field allows the intelligent reader to formulate a comprehensive concept regarding etiological factors and pathogenesis of atherosclerosis. Its impact on pre­ ventive and curative medicine was however limited in scope.