The medical records of 109 patients who presented to the emergency department during a five-year period with proven nontraumatic, spontaneous subarachnoid hemorrhage (SAH) were retrospectively reviewed. The clinical presentation, diagnostic modalities used, and accuracy of diagnosis by emergency physicians were analyzed. The most common historical features were headache (81 patients, or 74%), nausea or vomiting (85 patients, or 77%), and loss of consciousness (58 patients, or 53%). Nonexertional activities preceding SAH were more frequent than exertional events (57% vs 21%). Neurologic findings were present in 70 patients (64%) and consisted primarily of altered levels of consciousness. Thirty-eight patients (35%) had nuchal rigidity. Ninety-six emergency cranial computed tomography scans were performed, of which 91 were diagnostic for SAH (sensitivity, 95%). Lumbar puncture was performed on two patients with normal computed tomography scans and revealed bloody spinal fluid. The overall diagnostic accuracy by emergency physicians was 85%. The correct diagnosis was delayed in 16 patients (15%), the majority of whom had headaches and normal neurologic examinations. Atypical symptoms, the warning leak syndrome, and the need for prompt diagnosis and therapy are reviewed.