Background: Respiratory insufficiency associated with morbid obesity can include sleep apnea syndrome (SAS), obesity hypoventilation syndrome (OHS), or a combination of both. The aim of our study was to determine the safety and effectiveness of vertical banded gastroplasty (VBG) in the treatment of severely obese patients with respiratory insufficiency. Methods: From 1983 to 1994, 35 patients (25 males, ten females) who met the criteria for either SAS and OHS (19 patients) or SAS alone (16 patients) underwent VBG. Results: Six patients (17%) died of subsequent pulmonary-cardiac disease despite significant weight loss. Need for nasal continuous positive airway pressure (CPAP) decreased after VBG from 68% of patients preoperatively to 22% postoperatively. Of the ten patients with sleep studies, the apnea/hyponea index decreased from 45 ± 11 events per h preoperatively to 12 ± 6 events per h postoperatively, while per cent ideal body weight (%IBW) also decreased (pre-VBG: 268 ± 12, post-VBG: 204 ± 12). Of the seven patients with arterial blood gases, PaCO₂ decreased from 55 ± 4 torr preoperatively to 41 ± 3 torr postoperatively, and PaO₂ increased from 50 ± 4 torr preoperatively to 73 ± 6 torr postoperatively, while %IBW decreased (pre-VBG: 263 ± 16, post-VBG: 193 ± 14). Conclusion: Respiratory insufficiency is a life-threatening complication of morbid obesity. In morbidly obese patients with respiratory insufficiency, VBG offers improvement in both SAS and OHS. Respiratory insufficiency due to obesity should be considered a strong indication for VBG.