After Leksell and Steiner's pioneering experience with the use of the gamma units, another technically different system has been developed, using a linear accelerator. It's a very precise stereotactic radiosurgical approach which allows to deliver the necessary dose of radiation to the target volume while sparing the surrounding structures from potentially dangerous levels of radiation. This hyperselective irradiation is a new and complementary method of treatment of arteriovenous malformations located in central or functionally critical areas of the brain. The aim is to obtain a progressive and total obliteration of the lesion. The place of radiosurgery is obviously reserved for the patients who do not seem able to profit from the benefits of open surgery and/or embolization techniques.