The management of suspected and/or unsuspected common bile duct (CBD) stones in patients undergoing laparoscopic cholecystectomy (LC) is controversial. Decisions on whether to perform an open CBD exploration versus employing therapeutic options such as preoperative/post-operative endoscopic retrograde cholangiography (ERCP) or endoscopic duct exploration are polemic. To determine indications, timing, benefits, and potential morbidity of these approaches, we gathered data on 401 patients undergoing LC within the last 18 months. Indications for preoperative ERCP included jaundice (40%), dilated ducts (28%), elevated amylase (19%) or alkaline phosphatase (21%), suspicion of CBD stones by ultrasound (17%) and "other" (17%). Indications for postoperative ERCP were retained stones (33%) and CBD evaluation (67%). Indications for CBD exploration included abnormal cholangiogram (64%), palpable stones (18%), and other (18%). A significant correlation was observed between suspected stones by ultrasound and stones found by ERCP (P < 0.01). For patients in the "other" category, preoperative ERCP was universally negative (P = 0.04). Overall ERCP morbidity was 4/59 (6.8%), and the overall failure rate for clearing CBD stones was 2/28 (7.1%). The timing of the ERCP did not affect morbidity/mortality. Multivariate analysis revealed that age (P << 0.001), the presence of pre-existing medical risk factors (P << 0.001), and duration of LC (P = 0.0034), but not ERCP (P = 0.08), were the important factors determining LC morbidity. In summary, common bile duct stones can be successfully cleared endoscopically in the majority of patients undergoing LC. Patients with suspected CBD stones should undergo pre-operative ERCP, and strict criteria should be applied in the selection of these patients.(ABSTRACT TRUNCATED AT 250 WORDS)