Two hundred twenty-three cases of inverted papilloma seen at this institution over a 35-year period were reviewed. The number of cases steadily increased over each 5-year period. Common presenting signs and symptoms, association with carcinoma, and results of surgical and radiographic treatment are presented. The pathologic controversy surrounding this disease is discussed, and an argument is made for including all pathologic subtypes and septal, lateral wall, or sinus cases in a common clinical grouping of inverted papilloma. Lateral rhinotomy was found to be associated with fewer recurrences and a better probability of cure than lesser procedures and is recommended as the standard surgical therapy. Radiotherapy was found to be a useful and effective adjunct in cases associated with malignancy or for multiply recurrent and inoperable benign inverted papillomas. Lifelong follow-up is urged.