A retrospective study of the complications of treatment with the carbon dioxide (CO 2) laser of 17 patients diagnosed to be suffering from recurrent laryngeal papillomatosis is presented. No immediate complications occurred except one case of laryngospasm and failure to intubate during anaesthesia leading to hypoxic encephalopathy. Three patients were completely free from disease and complications. Another patient was free from laryngeal lesions but developed a papilloma in the right tonsillar pillar.