Pituitary tumors represent 10% of all intracranial neoplasms. Routine examination of pituitary glands at autopsy has disclosed that the prevalence rate of microadenomas may be as high as 25%.1,2 The diagnosis and management of pituitary tumors have been revolutionized by five developments in the recent past—the emergence of high-resolution computed tomography (CT), the development of sensitive radioimmunoassays (RIAs) for measurement of adenohypophyseal hormones, improved histological staining techniques, expertise in transsphenoidal microsurgery, and the availability of adjunctive drug therapies. These developments have contributed significantly to the early detection and better management of patients with pituitary tumors. These tumors, considered benign in terms of their nonmetastatic proclivity, often demonstrate a locally aggressive behavior, resulting in compromised sight and life. The morbidity caused by pituitary tumors relates to both the mass effect as well as the hormonal effects secondary to the tumor; the latter can be due to both hypersecretion of hormones by the tumor as well as deficient secretion of hormones by the normal portion of the gland compressed by the tumor. These morbid consequences can be prevented by instituting therapy early in the course of the disease.