Verrucous carcinoma is a well-differentiated squamous cell carcinoma with minimal cytologic atypia. Characteristically, the surface shows papillary fronds with prominent hyperkeratosis. Its benign appearance makes diagnosis difficult and often delays treatment. This is a review of 52 histologically confirmed cases of verrucous carcinoma of the larynx treated at the Mayo Clinic between 1960 and 1987. The follow-up ranged from 2 to 304 months. The most common primary treatment modality was surgery. Two patients died of laryngeal cancer. In both cases, the recurrence was a high-grade carcinoma histologically distinct from the original verrucous carcinoma. The T stage, clinical stage, and type of surgical excision failed to predict survival. The presence of extensive leukoplakia surrounding the exophytic tumor approached statistical significance (p = .08) in predicting recurrence. Four patients were treated with radiotherapy--in each, to control residual disease. One of these patients developed a local recurrence. None of the irradiated tumors in this series showed anaplastic dedifferentiation, and none of the irradiated patients died of uncontrolled local or regional disease. We conclude that verrucous carcinoma of the larynx should be treated by conservative surgical resection when possible. Radiotherapy can be effectively used for disease that cannot be resected with preservation of laryngeal function. Total laryngectomy should be reserved for recurrent disease or the rare case of anaplastic transformation.