The results of a retrospective comparative study of 122 patients who underwent explorations of the common bile duct in a district general hospital over a 5-year period are presented. Seventy-eight patients had a supraduodenal choledochotomy, 32 had a transduodenal spincterotomy and 12 had a combination of both procedures. Particular attention was paid to postoperative complications in relation to the grade of the surgeon performing the operation and also to the age of the patient. A total of 78 (64 per cent) patients had definite stones in the common bile duct. Of these patients, 7 (9 per cent) were subsequently shown to have retained stones, all having been operated on by registrars. Registrars also did more negative explorations than consultants. Nine patients (7.4 per cent) died, all but 1 of them being over the age of 70 and 4 of them having had a combined procedure. We conclude that transduodenal exploration should be avoided in patients over 70, particularly when added to a supraduodenal exploration.