Microendoscopic treatment of hypopharyngeal (Zenker's) diverticulum was performed in 31 patients during the period 1990-1995. The CO2 laser combined with the operating microscope has been used. 33 endoscopic procedures were performed (2 procedures were needed for 2 patients). The average age of the patients was 70.3 years (46-86 years). The average length of the general anesthesia was 48 minutes; the average length of the endoscopic procedure was 20 minutes. No major complication occurred for 32/33 cases (97%). Mediastinitis occurred for 1 case (3%) and was successfully treated by surgical and IV antibiotherapy. The average duration of hospitalization was 5 days (3-5 days) (patient with mediastinitis excluded): the average follow-up was 19 months (1-62 months). 28/31 patients (90.3%) were highly or fairly satisfied. Considering the external approach microendoscopic CO2 laser diverticulotomy offers comparable functional results. Moreover, this procedure is quick, requires a shorter hospitalization stay and is followed by a very low percentage of complications. Additionally, no visible scar is noted. Optimal management of Zenker's diverticulum remains controversial. However, we advocate that microendoscopic CO2 laser diverticulotomy should be considered as a first-line treatment option for patients with hypopharyngeal diverticulum.