Nasal polyposis in an infrequent condition in children and may occur as part of a variety of diseases. Treatment is difficult and often yields disappointing results. The purpose of this paper is to review the diagnostic problems raised by nasal polyposis and to analyze current surgical approaches. Twenty-seven patients with a mean age of 12 years, including 12 with nasal polyposis as part of another disease state (cystic fibrosis in 10 and Woakes disease in 2) and 15 with idiopathic nasal polyposis, underwent endonasal ethmoidectomy. The decision to perform this procedure was based on severity of initial clinical symptoms, lack of improvement under medical treatment, and availability for close postoperative follow-up. Twenty-six patients were followed-up for a mean period of three years ad a half. Complete recurrence occurred in 15% of patients and partial recurrence in 8%. In all the other cases, the ethmoidal cavity was satisfactory and nasal symptoms resolved completely. Etiopathogenic aspects of nasal polyposis are reviewed, as well as the therapeutic approach according to whether or not the disease occurs as part of another syndrome.