Reversible cerebral vasoconstriction syndromes (RCVS) comprise a set of conditions having in common the apoplectic onset of headache mimicking subarachnoid hemorrhage, focal or multifocal neurologic deficits with a predilection for visual processing disorders, multifocal vasoconstriction on cerebral angiography, noninflammatory spinal fluid, and a generally benign prognosis. RCVS may occur in the setting of the puerperium, after intracranial surgery, in association with prescription or illicit drug use, in migraineurs, or without a clear trigger. Distinction from central nervous system vasculitis is important and is often possible using routine clinical assessment, without brain biopsy. No treatments are of proven value in RCVS. Empiric treatments include the use of calcium channel blockers, steroids, induced hypertension or blood pressure lowering, and rarely endovascular therapy. The key to successful management is accurate diagnosis and cognizance of the tendency of RCVS to resolve without long-term immunosuppressive treatment.