A 65-year-old man had nightmares a few weeks after a right temporal lobe infarction. Electroencephalography showed no epileptic activity. Therapy with diphenylhydantoin produced complete remission of his symptoms. On the bases of their acute onset, their association with sleep, their occasional occurrence while the patient was awake, the lack of effect of diazepam and flurazepam, and the good response to diphenylhydantoin, we propose that these episodes were partial seizures secondary to the right temporal lobe lesion.