Twenty years' experience with the surgical treatment of Zenker's diverticulum is discussed, with emphasis on 25 patients treated by the Dohlman endoscopic method since 1959. In these patients, mostly elderly, the sac was not removed, but the wall between the esophagus and pouch was divided endoscopically. There were no deaths and no instances of mediastinitis or hemorrhage. Twenty-four of the 25 patients were able to eat with much greater ease. The chief advantages of the endoscopic approach are its extreme brevity of two to five minutes, lack of morbidity, and lack of threat to the recurrent laryngeal nerve. Reoperations are as simple as the original.