The clinical and pathological features of 100 consecutive cases of primary carcinoma of the gallbladder, treated by a single surgical unit, are described. Females out numbered males by 2 to 1. The maximum incidence was seen in the fifth decade. Pain and the presence of a mass were the two most common clinical features. Gallstones coexisted in 45 per cent of cases. Ancillary investigations were of little value in preoperative diagnosis. At laparotomy biopsy alone was possible in a large number of cases owing to the advanced disease process. Two patients were alive 5 years after surgery. Prophylactic cholecystectomy for all diseased gallbladders, whether symptomatic or not, is advocated.