Recurrent, severe, and intractable symptoms of right upper quadrant abdominal pain without a clear cause are extremely frustrating to patients and their physicians. This study examines the use of strict preoperative criteria utilizing endoscopic retrograde cholangiopancreatography, strictly defined clinical symptoms, and laboratory values to identify patients with hepatobiliary or pancreatic pain resulting from abnormalities of the papilla of Vater and the duct of Wirsung. Microscopic sphincteroplasty techniques stressing complete transection of the muscular transampullary septum have been incorporated with strict preoperative screening criteria to produce significantly improved long-term results (p greater than 0.005). Sixty-eight percent of 81 highly selected patients with at least a 6 month follow-up reported good results. Ninety-four percent claimed the procedure was definitely of benefit.