The incidence of chronic rheumatic valvular heart disease in Iceland was investigated via autopsies performed from November 1965 through December 1974. During this period, approximately 12.400 Icelanders died at the age of 16 years and older and 28.8 per cent of these are included in the study. At autopsy, males were found to outnumber females by 2:1. Rheumatic valvular heart disease was found in 38 subjects, i.e. in 1.08 per cent of the cases, the sex distribution being 0.67 per cent males and 1.83 per cent females. As regards the hearts with chronically deformed valves, the deformity was of rheumatic origin only in 20 per cent of the cases; the majority, or 69 per cent, presented calcified aortic stenosis. Hospital records applying to most of the subjects were available and according to these, only 18 per cent disclosed a history of rheumatic fever. The diagnosis of rheumatic valvular disease was first established at autopsy in 71 per cent of the cases. An evaluation of the functional derangements of the diseased valves was not attempted, but there is reason to believe that many of the lesions were too mild to provoke significant symptoms and signs. Previous doubts about the existence of rheumatic heart disease in Iceland have been settled in this study.