During a 10-year period 2610 patients were operated on for biliary lithiasis; in 225 (8.6 per cent) cases the operation concluded with a choledochoduodenostomy. The commonest preoperative diagnosis (62.2 per cent) in these 225 patients was choledocholithiasis; 30 patients had previously had a cholecystectomy. After choledochoduodenostomy, 4.0 per cent of patients had an intra-abdominal complication; six patients developed an intra-abdominal abscess and three developed an external biliary fistula. Four patients (1.8 per cent) died, three from pulmonary complications and one from a biliary fistula. After a mean follow-up period of 4.6 years, 71.5 per cent of patients were asymptomatic. The remainder suffered from dyspepsia (15.1 per cent), colicky pain (8.7 per cent) or episodes of cholangitis (4.7 per cent). Endoscopy in the symptomatic patients allowed the following conclusions: (a) no patient with dyspepsia had a problem at the anastomosis; (b) 27 per cent of those with colic had anastomotic stenosis or the sump syndrome; and (c) all patients with cholangitis had anastomotic stenosis and residual calculi.