A 16-year (1965-1980) retrospective clinical study of septicemia and endocarditis was performed at a hospital for infectious diseases. 634 patients (74.5%) had septicemia, 138 (16.2%) endocarditis and 79 (9.3%) suspected endocarditis. The mean age was 55 years, 472 were males and 379 females. Predisposing underlying conditions were recognized in 89.2%. Gram-positive cocci (62.3%) dominated over gram-negative rods (29.5%). The most common causative organisms of septicemia were Staphylococcus aureus (22.4%) and Escherichia coli (20.2%), and of endocarditis, S. aureus (47.1%) and alpha haemolytic streptococci (21.0%). The overall fatality rate was 17.7% and was highest in infections caused by gram-negative rods and S. aureus. In septicemia the rate was 15.3% and in endocarditis 37.0%. Unfavourable prognostic factors were high age, endocarditis and underlying conditions such as haematological diseases and various other factors.