Endobiliairy tissue specimens were obtained for cytologic and histologic examinations at the site of stenosis after percutaneous biliary drainage or endoscopic retrograde sphincterotomy in 49 patients with benign (10 cases) or malignant (39 cases) biliary stricture. Final etiologic diagnosis was obtained by surgery (18 cases), autopsy (one case), aspiration cytology of metastasis (2 cases), serology (2 cases), and in 26 cases, was determined by the course and outcome of the disease. As the sensitivity of each method, cytology and histology, was weak, it was necessary to associate them to improve results. Accurate etiologic diagnosis was achieved in 77 p. 100 of cases. The specificity of the method was satisfactory and specimen examination allowed to correct and confirm the initial etiologic diagnosis in 12 and 65 p. 100 of cases, respectively. The specificity of the method and its low morbidity prompt us to recommend it during transhepatic or retrograde therapeutic drainage as it can serve as a guide for later treatment. On the other hand, achievement of a transhepatic drainage or an endoscopic sphincterotomy only to obtain endobiliairy tissue specimens means taking into account the poor sensitivity of the method and the complications inherent to transhepatic drainage and endoscopic sphincterotomy. The practice of obtaining specimens by the retrograde technique without sphincterotomy or under cholangioscopy should be developed.