Purpose/Objective(s): To report outcomes of patients with laryngeal or hypopharyngeal carcinoma treated with definitive intensity-modulated radiation therapy (IMRT). Materials/Methods: The clinical records of all patients with laryngeal and hypopharyngeal squamous cell carcinomas treated with definitive IMRT at our institution between January 2004 and December 2011 were retrospectively reviewed. Fifty patients were reviewed. All patients would have required a total laryngectomy. Forty-two (84%) patients received concurrent chemotherapy, 6 (12%) received no chemotherapy, and 2 (4%) received adjuvant chemotherapy. Of patients who received concurrent chemotherapy, the majority of them (24 patients, 48%) received cisplatin alone; 6 patients (12%) received cetuximab alone, 8 (16%) received both cetuximab and cisplatin, and 6 (12%) received other chemotherapy regimens. Kaplan-Meier survival analysis and univariate Log-rank statistics were applied. Results: Median follow-up was 26.0 months (range, 4.0-106.0 months). Median age was 61 years (range, 35-83 years); 39 (78%) were male. There were 35 (70%) laryngeal and 15 hypopharyngeal cancers. Twelve (24%), 29 (58%), and 2 (4%) patients were diagnosed clinical stages III, IVA, and IVB, respectively. All patients were prescribed 7000 cGy in 35 daily fractions; however, 2 patients were unable to complete the full treatment. There were 16 local, 7 regional, and 15 distant failures. For all patients, local control (LC), locoregional control (LRC), and overall survival (OS) at 2 years were 73%, 68%, and 63%, respectively. The 2 year LC, LRC and OS for laryngeal cancer were 77%, 75%, and 70%, respectively. For hypopharyngeal cancer, LC, LRC, and OS at 2 years were 54%, 45%, and 47%, respectively. LC and LRC were not significantly different between sites, but there was a trend toward improved OS in patients with laryngeal cancer, (P Z 0.06). Eleven patients underwent salvage laryngectomy (9 laryngeal and 2 hypopharyngeal). Altogether, 34 (68%) patients had a feeding tube placed; 6 (12.5%) before, 25 (50%) during, and 3 (6%) after radiation therapy. At the time of last follow up, only 14 patients (28%) remained feeding tube dependent. Outcomes looking at tumor volume, CTV expansion, and other dosimetric properties will be reported later. Conclusions: The use of IMRT achieved encouraging local and regional tumor control in patients with hypopharyngeal and laryngeal cancer. There is a trend toward worse overall survival in patients with hypopharyngeal compared to laryngeal carcinoma. Feeding tube placement and dependency were common treatment related toxicities but were preferred to the loss of a lung powered voice. Author Disclosure: C. Kreofsky: None. Y.I. Garces: None. D.L. Price: None. K.A. Price: None. R.L. Foote: None.