The endoscopic transnasal approach is an evolving technique for treating lesions in the sella turcica. Since this method was introduced at our institution 4 years ago, the majority of transsphenoidal procedures are performed with it. The records of all patients having endoscopic transnasal hypophysectomy at the Mayo Clinic during the last 4 years were reviewed retrospectively. The criteria analyzed were safety, functional and cosmetic outcome, and complications. During the 4-year period, the operative procedure was modified to improve operative exposure and safety. The results of our review showed a significant decrease in length of hospital stay, reduced operative time, reduced need for nasal packing, and elimination of a sublabial incision. The complication rate was equivalent to that reported for the traditional transseptal transsphenoidal approach. As the neurosurgeons at our institution gained experience with this approach, an increasing number of pituitary microadenomas were resected safely and successfully. In addition, because of the limited septal dissection, this approach is particularly helpful for revision operations. This approach also can be used for the full range of pituitary lesions and in conjunction with adjunctive techniques, including frontal craniotomy and gamma-knife irradiation. Currently, the endoscopic transsphenoidal approach is the method preferred for surgically treating pituitary lesions in adults at our institution.