We reviewed the clinical courses of 37 patients treated for pyogenic liver abscesses. These abscesses were cryptogenic in 38% of the patients, associated with biliary tract or intra-abdominal disease processes in 48%, and hematogenous in 11%. Computed tomography was more accurate (96%) in diagnosing a hepatic abscess than ultrasonography (82%). The majority of the patients were treated initially with percutaneous drainage (18) or needle aspiration drainage (5); treatment failure occurred in 9 of these 23 patients (39%). In contrast, there were no treatment failures in the 9 patients treated with primary operation. Overall, 4 of the 37 patients died (a mortality rate of 11%) but 2 of them died of underlying malignant disease rather than the liver abscess.