One hundred and twenty two patients with postcholecystectomy syndrome were studied by endoscopic retrograde cholangiopancreatography (ERCP). The procedure was successful in 105 patients (85.3%) and it accurately detected abnormality of the pancreatico-biliary system in 71 patients (67.6%). ERCP results were abnormal in 82.6% of patients with biliary symptoms, with or without jaundice, compared with 34.7% of patients with non-biliary symptoms (P less than 0.001). Though ERCP showed abnormality in all patients with biliary symptoms and jaundice, as many as 70.4% of patients without jaundice had abnormal ERCP. The commonest abnormality was retained/recurrent stones (37/105 patients). Patients with biliary strictures presented significantly more often with jaundice compared with patients with biliary stones (74.3% vs 22.3%). In 19 of the 37 patients with retained biliary stones endoscopic sphincterotomy was performed and it was successful in 16 patients (84.2%). Our data indicates that ERCP detects the anatomical level as well as the nature of lesion accurately, and is essential and safe in the diagnosis and management of patients with postcholecystectomy syndrome.