Interventional neuroradiology is the catheter-based therapy for vascular lesions of the brain and spine. During the past decade, the field has expanded rapidly, and ongoing technical developments are improving the application, safety, and efficacy of this therapy. A growing number of intracranial disorders are amenable to endovascular interventions, which include aneurysms, vasospasm from aneurismal subarachnoid hemorrhage, arteriovenous malformations, dural arteriovenous fistulas, intracranial tumors, thromboembolic occlusion of intracranial arteries and atherosclerosis. Interventional procedure alone is able to treat patients with diseases that cannot be treated with neurosurgery and radiation ; however, in many cases a combination of these methods provides the best outcome for the patients. Treatment strategies must be developed in collaboration with other neurological sciences and experienced multidisciplinary teams must be responsible for handling of patients with CNS lesions. Both education in practical skill and ethics must be part of structured training programs in especially assigned neurointerventional centers.