Inverted papillomas arising from the lateral nasal wall are controversial lesions which have been reported in the medical literature under a variety of titles. The designation "inverted Schneiderian papilloma" is recommended as an appropriate title to best convey the tumor's qualities of inversion, location, and distinctiveness of character. The etiology is uncertain. In the absence of a better explanation of its origin, the tumor should be considered a true epithelial neoplasm. Clinical features in 101 cases seen at the Geisinger Medical Center during the past 25 years are presented. The most frequent presenting complaint was nasal obstruction. The site of origin was the lateral nasal wall in the region of the middle meatus. The most characteristic attributes of the tumor were its tendency to recur, its destructive capacity, and its propensity to be associated with malignancy. To illustrate the pernicious nature of the lesion, a detailed description is given of the extent of bone erosion, the extraordinary sites of tumor extension, and the perioperative complications encountered. A philosophy of management has evolved based on the experiences gained from these 101 patients combined with a review of the experiences of others and study of the regional anatomy. A bold surgical approach is detailed using a lateral rhinotomy incision or a modified Weber-Ferguson incision to expose the tumor adequately and remove it completely. The recurrence rate using this approach was 2%. An associated malignancy was present in 8 patients. Four died of widespread metastases within a year of the diagnosis. The remaining 4 patients are long-term survivors free of disease.