A patient operated upon for acalculous cholecystitis was later found to have Caroli's disease, congenital ectasis of intrahepatic bile ducts. Cholangitis, calculi and abscesses occurred in both lobes of the liver. Sepsis was not controlled despite open drainage, hepatic segmentectomy and ductal lavage with antibiotics and saline. At autopsy the liver contained a dozen unsuspected cavities filled with calculi, bile and pus. Diagnosis of Caroli's disease is best made by operative cholangiography in patients with atypical biliary disease. Management with antibiotics alone is seldom successful. Hepatic resection is better than drainage procedures for unilateral lesions. In patients with bilateral abscesses and no extrahepatic ductal obstruction or dilation, surgical treatment is often ineffective.