Non-traumatic subarachnoid hemorrhage (SAH) represents approximately 5-6% of all strokes. Morbidity and mortality rates remain high, but accurate diagnosis using clinical assessment and neuroimaging, critical care management, and early treatment using either surgical or interventional techniques have improved overall outcomes. This, the fifth in a Missouri Medicine series on stroke, summarizes the clinical and imaging aspects of making the diagnosis of SAH, critical care management of the patient, treatment options, and factors important in prognosis.