While a clinical history is frequently sufficient for a localizing diagnosis of temporal lobe epilepsy, lateralization of the epileptogenic abnormality often is impossible on clinical grounds alone. Since we have noted facial asymmetry in such patients, 50 individuals with temporal lobe epilepsy were studied. In patients with unilateral foci, we found contralateral lower facial weakness of mild to severe degree in 73 percent while 13 percent had ipsilateral weakness, and in 13 percent the face was symmetrical. The facial weakness usually was more striking on emotional movement. In the group of patients with bitemporal independent discharges, 61 percent had some asymmetry, often facial weakness on the side opposite the major focus. Of 25 control individuals, only one third had a facial asymmetry and this was slight. Facial asymmetry in temporal lobe epilepsy is a useful though not an absolute clinical lateralizing sign. It is a factor to be considered in addition to other clinical, radiologic, neuropsychologic, and electroencephalographic findings in the evaluation of patients with temporal lobe seizures.