All 519 endoscopic pancreatograms performed in the Massachusetts General Hospital Endoscopy Unit from 1973 to 1980 were reviewed. Patients who underwent pancreatograms for documented pancreatitis were more likely (p less than 0.005) to have the duct anomaly pancreas divisum (12%) than those patients who had pancreatograms incidental to cholangiography (2.9%), or for unexplained chronic abdominal pain (3.3%). When compared with patients with pancreatitis and normal duct development, patients with pancreatitis associated with pancreas divisum tended to be younger and to have a clinical pattern of recurrent acute attacks of pancreatitis. Nine patients with recurrent pancreatitis or severe chronic abdominal pain and pancreas divisum were treated by surgical sphincteroplasty of the accessory ampulla. Five of the 6 patients with documented acute attacks of pancreatitis received good to excellent pain relief and had no further attacks of acute pancreatitis. None of the 3 patients with severe chronic abdominal pain without objective evidence of pancreatitis derived significant benefit. Accessory ampulla sphincteroplasty seems to relieve pain and prevent further attacks of acute pancreatitis in patients with pancreas divisum and recurrent pancreatitis. This response to sphincteroplasty adds further credence to the stated association between pancreas divisum and pancreatitis.