The introduction of transnasal endoscopic surgery has revolutionized the surgical treatment of several malignant tumors which are accessible via a transnasal route. The main target anatomic areas are the sinonasal tract, the nasopharynx, and the clivus. Malignancies originating in these sites are characterized by a marked heterogeneity in histology and biological behavior, making it imperative that treatment of every single case is discussed by a multidisciplinary team with specific expertise. Primary surgery is indicated in a large number of malignancies involving the sinonasal tract and the clivus, while for nasopharyngeal cancer surgery may prevalently play a role as a salvage treatment in selected lesions. The experience collected during the last two decades in transnasal endoscopic surgery of malignant tumors has led to accurately assess indications, limitations, and advantages as well as outcomes in terms of survival and morbidity. Based on their longstanding experience, the speakers will review the role of transnasal endoscopic surgery in the context of a multidisciplinary management of malignant tumors of the sinonasal tract, nasopharynx, and clivus. Details on patient selection and surgical techniques together with an analysis of survival outcomes, complications and their management, post-treatment surveillance, pattern of recurrence, and possibilities of salvage treatment will be provided.