Endoscopic retrograde cholangiopancreatography (ERCP) was carried out in 98 patients with unexplained abdominal pain or known pancreatitis with recurrent pain. Patients with jaundice were excluded from the study. In 38 patients with a clinical diagnosis of pancreatitis, the radiological findings on ERCP were graded according to the criteria of Kasugai et al. Advanced pancreatitis was found in 20 patients (52,5%), moderate changes in 7 (18,4%) and minimal-change pancreatitis in 6 (15,8%). ERCP had normal pancreatic function tests. In 35 patients investigated for unexplained abdominal pain, changes consistent with pancreatitis were found in 7, pancreatic carcinoma in 5, a duodenal ulcer in 2, gallstones in 1 and a duodenal tumour in 1. ERCP was normal in 19 patients. A comparison of the findings on ERCP and the standard secretin-cholecystokinin pancreatic function test was available in 52 patients. There was a good agreement between the two tests in the patients with advanced or moderate pancreatitis as revealed by ERCP, but less agreement in the patients with minimal-change pancreatitis. A few patients with clinical pancreatitis and abnormal ERCP had normal pancreatic function tests. ERCP increases the diagnostic yield in patients suspected of having pancreatitis and is at present the only reliable method of diagnosing pancreatic carcinoma which is not evident by other non-operative techniques. ERCP is also of value in the assessment of the severity of pancreatitis and is a necessary investigation before pancreatic surgery to confirm or exclude cyst formation or the site of duct obstruction. The finding of an unsuspected cyst at ERCP necessitates early operation because of the danger of introducing infection during the procedure.