Since 1954, 840 patients have been treated at Lawrence Berkeley Laboratory with stereotactic charged-particle radiosurgery of the pituitary gland. The initial 30 patients were treated with proton beams; the subsequent 810 patients were treated with helium ion beams. In the great majority of the 475 patients treated for pituitary tumors, marked and sustained biochemical and clinical improvement was observed. Variable degrees of hypopituitarism developed in about one-third of patients treated solely with radiosurgery. In the earlier years of the program, 365 patients underwent radiosurgery to treat selected systemic diseases by inducing hypopituitarism. Focal temporal lobe necrosis and cranial nerve injury occurred in about 1% of patients who were treated with doses less than 230 Gy.