This is a review of 65 patients with paranasal sinus malignancies who were treated by radical surgery. Most patients received either pre- or postoperative radiotherapy. Twenty-nine tumours arose in the maxillary antrum, seventeen in the ethmoid labyrinth and the remainder from the vestibule, nasal septum, lateral nasal wall and vault. There were 58 epithelial cancers. The 5-year survival rate for patients with adenocarcinoma was 78%, and 70% for antral squamous cell cancer and esthesioneuroblastoma. None of the melanoma patients survived free of disease for 5 years. The 5-year survival rate for the 21 patients undergoing orbital exenteration was 50%, compared with 70% when the eye was spared. Twelve free flap revascularized tissue transfer flaps were used to reconstruct large cranial and sino-orbital defects.