BACKGROUND: Residual stones after biliary tract surgery are a formidable task for the surgeon. Choledocholithiasis and hepatolithiasis are more common in East Asia, including Korea, compared with the West, and retained and recurrent stones remain a major problem after the surgical treatment of biliary tract stones; thus, various attempts to reduce the rate of retained and recurrent stones are important in the treatment of biliary tract stones. METHODS: A retrospective analysis was done on 815 cases of patients with biliary tract stones who had undergone an operation at the Department of Surgery, Chung-ng University Hospital, during the 13 years from January 1984 to December 1996. RESULTS: The male-to-female sex ratio was 1 : 2, and the most common age group was the 7th decade. The most common symptoms and physical findings were right upper quadrant pain in 620 cases (76.1%), and right upper quadrant tenderness in 511 cases (62.1%). The most common laboratory findings were elevated alkaline phosphatase (88.3%), followed by elevated sGPT and elevated sGOT. Bile cultures and sensitivity tests were done in 815 cases and were positive in 682 cases (83.7%). The most common bacteria were E.coli in 252 cases (37.0%). The locations of the stones were gallbladder (GB) and common bile duct (CBD) in 420 cases (51.5%), the CBD in 160 cases (19.6%), the CBD and intrahepatic duct (IHD) in 108 cases (13.3%). The most common operative procedure was a cholecystectomy with T-ube insertion, 525 cases (64.4%). Postoperative complications developed in 208 cases (25.6%), and the most common postoperative complication was wound infection, 72 cases (8.8%). The operative mortality was 2.9%, and most common cause of death was sepsis (10 cases). CONCLUSIONS: The authors conclude that interventional therapy, as an initial treatment for residual stones, is a satisfactory treatment where possible. If there are residual stones in spite of the interventional therapy, a reoperation or hepatectomy is required.