Radiosurgery refers to the possibility of the destruction of a small area in the brain with a high dose of radiation, after determination of the target with stereotactic coordinates. Arteriovenous malformations of small size not treatable by direct surgery are obliterated by radiosurgery in nearly 80 p. 100 of the cases. Cerebral metastasis are also effectively treated with a good local control, especially in case of small solitary lesion. In acoustic tumor, of small and medium size, radiosurgery appears to be an alternative to surgery. Other benign tumors (meningioma, pituitary adenoma) have also been treated, but long-term studies are still necessary to evaluate the efficacy of this technic.