From an anatomical standpoint, the nasal septum makes up the greater part of the bridge, contributes to determination of the length of the pyramid, plays a part in the formation of the columella, projects the tip and divides the space located behind the piriform orifice to limit the two nasal fossae. Deformities may thus affect the morphology of the pyramid and nasal physiology, in other words require correction for aesthetic or functional reasons. These two aspects of the question are considered in succession, with the understanding that the two problems often exist in association, in particular after trauma. Surgical action involving the septum is almost always associated with the operative protocol of a rhinoplasty for aesthetic purposes. Emphasis has been placed above all on operations for functional purposes. Three techniques are discussed: resection and reposition, considered to be procedures involving the septum only, and rhinoplasty where the operation involves the whole of the pyramid. There is no basis for the automatic rejection of any of them, but on the contrary all are valid and mutually interrelated by multiple forms of passage and association.