FEW operations are more distressing to the patient bile-duct in almost 75 per cent. These figures and the surgeon alike than re-exploration of the suggest that the standard methods of exploring the biliary passages. Preston (1959, reporting on 74 biliary passages are frequently inadequate. consecutive and unselected postoperative cholangioThis article puts forward the case for duodenograms, found that 43 per cent showed persistent tomy and transduodenal choledochoduodenostomy abnormalities at the distal end of the common bile-(sphincterplasty) as a useful and reliable surgical duct and residual stones were demonstrated in procedure to ensure patency of the biliary passages 24 per cent. Other reports on the incidence of recurrent or residual stones in the biliary passages give a figure of between 2 and 28 per cent. Moreover, the incidence of recurrent or residual stones is higher after a previous positive exploration of the common bile-duct than after a negative exploration, and a history of multiple operations on the hiliary passages is not infrequent in these patients (Jones, Smith, Keller, and Joergenson, 1963). In 69 patients requiring secondary exploration of the biliary passages, Mongk (1966) found stones in the common