Currently, surgical management provides the definitive treatment of choice for most pituitary adenomas, craniopharyngiomas and meningiomas of the sellar region. The elegant minimally invasive transnasal endoscopic approach to the sella turcica and the anterior skull base has added a new dimension of versatility to pituitary surgery and can be adapted to many lesions in the region. In this multi-author book with numerous color illustrations the main aspects of the endonasal endoscopic approach to the skull base are presented, starting with a clear description of the endoscopic anatomy, the panoramic view afforded by the endoscope and the development of effective instruments and adjuncts. After the diagnostic studies, the strictly surgical features are considered in detail. The standard technique is described and particular aspects are treated, including the new extended approaches to the cavernous sinus, spheno-ethmoid planum and clival regions.