SummaryOur investigation has brought forward :1°that a painful gallbladder may look quite normal to the surgeon. In this case cholangiography is necessary and conclusion from finger examination only has to be avoided ;2°that cholangiography alone may also be a source of error ;3°that radiomanometry of the biliary tract is very useful if completed by a study of the effects of atropine or papaverine. This helps to make clear the nature of the obstruction and also to localize it exactly;4°as X-rays pictures obtained during the operation without assay of papaverine or atropine do not always answer the question of the nature of the obstruction, it seems that this procedure has to be limited to well equiped surgical centers.Postoperative radiomanometry on the contrary is quite easy and requires only simple equipment. Of course it imposes a delayed operation, but the bad results of surgery in a large number of cases justify this method.