Laparoscopic cholecystectomy is commonly practiced by surgeons and the most worrisome complication is biliary tree injury. On 60 patients undergoing Laparoscopic cholecystectomy we injected Methylene blue dye into the gall bladder trying to delineate the biliary tree. Cystic duct was painted in 56 patients (93%) while common bile duct and hepatic ducts were painted only in 38 patients (63%). The technique is easy to perform, without any radiation exposure hazards, without using special equipment and is less time consuming than other maneuvers used to delineate the biliary tree during laparoscopic cholecystectomy. It is cheap and can be done even with no prior special experience in the technique. The incidence of bile system injury related to anatomic misidentification can be decreased or even totally avoided. It may be of value in thin wall gall bladder but in thick wall gall bladder it is of questionable value and needs more investigation.