The skull base is a meeting point for anatomical regions, surgical specialties, and surgical philosophies. Skull base surgery is a dynamic subspecialty and the last decade has witnessed the application of endoscopic techniques to the ventral skull base using an endonasal corridor. The transition from external approaches to an endonasal corridor has not been without controversy. In this volume, we explore the nascent field of neurorhinology, a term that emphasizes the multidisciplinary collaboration between neurosurgeons and rhinologic head and neck surgeons. Authors have applied evidence-based medicine techniques to critically evaluate the literature and attempt to answer some of the most important clinical questions. This first of two volumes focuses on the more common pathologies seen by Otolaryngologists in neurorhinology. Topics include: Spontaneous CSF leaks; Traumatic CSF leaks; Osteoma; Fibrous dysplasia of sphenoid and skull base; Orbital apex and orbit; Endoscopic endonasal transphenoidal resection of pituitary adenomas with adjunctive intraoperative magnetic resonance imaging; Craniopharyngioma; Tuberculum meningioma; Olfactory groove meningioma; Endoscopic endonasal surgery for nasal dermoids; Juvenile nasopharyngeal angiofibroma; Hypothalamic/ pituitary morbidity in skull base pathology