The challenge of this "decade of the brain" is to perfect the interventional means for detecting and treating vascular malformations. The prognosis for patients with aneurysms is improved with the introduction of the new Guglielmi detachable coils. Parent vessel occlusion is a good alternative for treating dysplastic aneurysms at the circle of Willis after functional testing. Vein of Galen malformations of the mural type are best treated using the arterial route. The venous route is useful for treating choroidal forms when treatment by the arterial approach fails. These advances have resulted in significant improvement in the outlook for children with these conditions. Arteriovenous malformation embolization with either particles or glue has about a 10% permanent complication rate and, when combined with radiosurgery or surgical resection, is successful in curing 74% of patients. Morphologic features within the arteriovenous malformation are statistically useful markers of clinical course (hemorrhage and steal). Carotid cavernous fistulas can now also be treated by microcatheter and coils through the arterial or venous routes. Angioplasty in the neck and intracranially results in improved cortical perfusion. With technologic improvements and better case selection, serious complications can be minimized.