Over the past two decades, the endoscopic endonasal approach has significantly expanded the armamentarium of minimally invasive skull base surgery. Initially developed for the treatment of pituitary adenomas, endoscopic endonasal skull base surgery (EESBS) has found increasing utility in managing a broad spectrum of skull base pathologies. Its application extends from the midline, encompassing the crista galli process to the occipitocervical junction, and laterally to the parasellar areas and petroclival apex. In recent years, there has been a notable shift from the exclusive use of endoscopic technology in endonasal pituitary surgery to other neuroendoscopic procedures. This chapter aims to provide the reader with an up-to-date overview of clinical trials on endoscopic neurosurgery of the skull base, brain, and neuroaxis. Through a comprehensive review of the state-of-the-art published peer-reviewed literature, the authors strive to offer a concise summary of the current concepts in this rapidly advancing field.