Four cases of cerebral edema associated with therapy for diabetic ketoacidosis are reported. One patient had an inappropriate ADH-like syndrome at the time of onset of clinical symptoms of cerebral edema; he survived. The remaining patients had hyponatremia at or near the time of onset of clinical symptoms of cerebral edema, and they subsequently died. The literature is reviewed and some aspects of therapy, which might be casually related to cerebral edema observed in association with therapy of diabetic ketoacidosis, are discussed.