The first case of posterior pharyngooesophageal diverticulum was published in 1764 by Ludlow. Zenker's name has been attributed to the diverticulum since his description of a series of patients in 1878. The aetiology and pathogenesis of Zenker's diverticulum are not well understood. Research has mainly focused on the role of the upper oesophageal sphincter, but numerous manometric studies have produced controversial results. Also, the influence of gastrooesophageal reflux on the upper oesophageal sphincter and the development of a diverticulum is unclear. Patients with a Zenker's diverticulum typically present with a long history of slowly progressive dysphagia for solid consistencies and regurgitation of undigested food. Weight loss and nocturnal attacks of coughing may bother the patient. The diagnosis of a diverticulum needs to be confirmed by radiologic examination. The only definite therapy is surgery. The classical extramucosal cricopharyngeal myotomy by transcervical approach, with or without removal of the diverticular sac, is increasingly giving way to transmucosal myotomy through a transoral endoscopic approach. Compared to the transcervical approach the endoscopic technique avoids the risk of injuring the recurrent laryngeal nerve, substantially lowers the number of pharyngeal fistulas and, in large series, showed an equivalent outcome as far as relief of symptoms is concerned. In the light of the literature and our own experience diverticulooesophagostomy with the Endo-GIA stapler by a transoral endoscopic approach has become the therapy of choice at the ENT-Department of the University Hospital of Zurich, Switzerland. In an operating time of only 10-15 minutes the stapler cuts the wall between the diverticular sac and the oesophagus, and in the same manoeuvre closes the mucosal wound edges with tiny staples. Oral feeding is possible from the first postoperative day. With the technique described this elderly population of patients obtains rapid and safe relief of symptoms.