Gallstones are commonly found within the main bile duct (MBD) of patients undergoing cholecystectomy. Retained MBD stones are a common cause of obstructive symptoms and complications. Endoscopic retrograde cholangiopancreatography (ERCP) and sphincterotomy (ES) is the recommended modality for both the detection of such stones and their extraction. Recent trials of ERCP in conjunction with laparoscopic cholecystectomy suggest that it should be reserved for use post-operatively. Gallstones within the MBD are the most common single cause of acute pancreatitis. Initial treatment is supportive, although new agents designed to suppress the systemic inflammatory response are under development and have proved beneficial in clinical trials. Severe cases should be treated with systemic antibiotics and early removal of the obstructing stones by ERCP and ES. Prophylactic cholecystectomy is recommended to prevent further attacks of gallstone pancreatitis.