Mirizzi's syndrome is the name given to common bile duct obstruction secondary to a stone in the cystic duct. The cause of the biliary obstruction is often difficult to establish before operation. We report two cases of Mirizzi's syndrome, diagnosed endoscopically and treated without surgery. One of the patients was treated by drainage of both the common bile duct and the gallbladder associated with monooctanoin dissolution of the gallstone. The other was treated by common bile duct stenting.