A study of 71 patients with obstructive sleep apnea syndrome was performed to evaluate the effectiveness, complications, and late sequelae of uvulopalatopharyngoplasty. Postoperative immediate complications were of minor importance. In 96% of the patients, the snoring was improved; it was completely resolved in 48%. The postoperative apnea index remained pathologic in all patients who underwent postoperative polysomnography, although mild improvement was noted. Seventy-four percent of our patients felt a subjective postoperative improvement which was not always confirmed by the polysomnographic examination. A record of improvement was obtained in 64% of the operated patients. Our results establish the beneficial effect of uvulopalatopharyngoplasty, which is the recommended surgical procedure for obstructive sleep apnea syndrome.