The authors report a series of 350 patients referred for clinical investigation of nasal polyps between 1980 and 1990. 93 patients were followed for more than 5 years. Allergy to inhalants was rarely found (2.8%). Detailed study of past rhinosinusal and bronchial symptoms often revealed a history of vasomotor rhinitis (nasal hyperreactivity HRN) preceding the nasal polyposis by a mean interval of 8 years. The ratio non-allergic vasomotor rhinitis/nasal polyps was 4.31 in women (41.4% of the patients) and 1.74 in men (58.6% of the patients). Treatment is usually based on the use of local corticosteroids. However, because of the variable clinical pattern of nasal polyposis treatment may be medical alone or both medical and surgical, and always requires a long clinical follow-up. Intolerance to aspirin is a factor of poor prognosis. A 15% failure rate was noted among patients intolerant to aspirin.