Fibromuscular dysplasia (FMD) is a nonatheromatous multifocal condition known to affect almost any systemic or brain-supplying artery, but this condition has special predilection for specific arterial sites. It tends to involve medium-sized muscular arteries, especially renal, splanchnic, and cervicocranial arteries. FMD can involve any or all of the three layers of the arterial wall, but disease of the arterial media is the most common and important form. The most common finding is alternating zones of widening and narrowing of the arterial lumen on angiograms, the so-called string of beads appearance. The most neurologically important associated conditions are intracranial aneurysms and arterial dissections. Intracerebral hemorrhages can develop because of the severe hypertension that sometimes accompanies renal artery FMD. CT angiography (CTA) and MR angiography (MRA) also can identify FMD lesions. Antiplatelet aggregating agents and calcium-channel blockers have been prescribed to prevent recurrent episodes of brain ischemia.