Syncope (passing out or fainting) or near syncope (lightheadedness or almost passing out) is a common reason for visiting an emergency department and most episodes are not serious. Many tests may be ordered to identify the cause of such episodes. However, diagnostic tests for syncope should not be routinely ordered, and the decision to order any tests should be guided by information obtained from the patient’s history or physical examination. CT scans of the brain are frequently ordered for this problem to look for bleeding or strokes, but published research has confirmed that abnormalities are rarely found. CT scans are expensive, and may unnecessarily expose patients to radiation. If a head injury is associated with a syncopal episode (fainting spell), then a CT scan of the brain may be indicated. In addition, if there were symptoms of a stroke (i.e., headache, garbled speech, weakness in one arm or leg, trouble walking, or confusion) before or after a syncopal episode, a CT scan may be indicated. However, in the absence of head injury or signs of a stroke, a CT scan of the brain should not be routinely ordered.