Arteriovenous malformations (AVMs) are congenital vascular abnormalities characterized by a complex, tangled network of arteries and veins without an intervening capillary bed. Although rare, AVMs can occur in cerebral, spinal, and extracranial locations, posing risks of hemorrhage, seizure, and neurologic deficits. This chapter reviews the current understanding of AVM pathogenesis, emphasizing abnormal angiogenesis, genetic predisposition, and hemodynamic factors. The role of radiation therapy—including stereotactic radiosurgery (SRS) and fractionated radiotherapy—is critically examined. We discuss radiation techniques (Gamma Knife, LINAC, CyberKnife), efficacy outcomes, and the significance of precise target volume delineation. We then overview toxicity profiles—both early and late effects—and elaborate on risk-mitigation strategies. A comprehensive literature review synthesizes key studies, including randomized trials and long-term outcome series, alongside illustrative case studies highlighting management dilemmas. Future directions focus on molecular-targeted radiobiology, image-guided adaptive therapy, combinatory embolization–radiation protocols, and the integration of artificial intelligence for treatment planning. Concluding remarks underscore the evolving role of radiation therapy within a multidisciplinary paradigm.