The presenting signs, symptoms, roentgenographic findings, endocrine evaluations, treatment, and results in 68 cases of presumed pituitary adenomas treated over an 18-year period are discussed. The most common symptoms were headache, acromegalic changes, visual symptoms, and amenorrhea. Most common physical findings were obesity, acromegaly, and visual field defects, usually bitemporal hemianopsia. Roentgenographic evidence of sellar erosion was almost universal but angiography and pneumoencephalography were required to evaluate suprasellar extension. Brain scan was not considered a particularly useful diagnostic tool. Endocrine status was best evaluated by a battery of tests including 17-OH, 17-KS, T3, T4, PBI, ACTH stimulation, and FSH and STH levels. (Prolactin levels are currently being obtained, also). Surgical specimens were obtained in 29 patients, with subsequent diagnoses of 22 chromophobe adenomas, five eosinophilie adenomas, one cystic adenoma, and one necrotic tumor. All five eosinophilic tumors came from acromegalic patients. Patients treated by operation alone or operation followed by radiotherapy generally had less "medical morbidity" than did patients who received radiotherapy alone.