BACKGROUND: Determining which patients benefit from larynx preservation strategies remains problematic. We reviewed our experience using multiagent concurrent chemoradiotherapy to identify clinical predictors for success. METHODS: Cisplatin and fluorouracil were given during weeks 1 and 4 of radiation to 115 patients with locoregionally advanced larynx or hypopharynx squamous cell cancer without cartilage invasion or laryngeal destruction. Laryngectomy was reserved for local failure. RESULTS: The 5-year Kaplan-Meier projected overall survival was 58%, survival with larynx preservation 52%, local control without surgery 82%, local control (including surgical salvage) 94%, and survival with functional larynx 49%. Local control without surgery was superior in patients with T1-2 versus T3-4 tumors (97% vs 77%, p = .032). No other clinical parameters proved predictive of local control. CONCLUSION: Larynx preservation was successful in all subsets of appropriately selected patients. Although local failure was more likely in patients with T3-4 tumors, it was infrequent and surgical salvage was effective.