This case is reported because the literature contains few records of cases of encephalitis complicating herpes zoster in which the brain was examined histologically after death. REPORT OF CASE History. —Mrs. L. V., a housewife aged 58, white, was seen by one of us (S. K.) in consultation on April 6, 1942, because she had become restless, noisy and irrational. She had been in relatively good health except for occasional headaches and backache, for which she was taking acetylsalicylic acid. On March 7 neuralgic pain developed in the left side of the face and neck. Two days later examination by the family physician revealed a herpetic rash over the lower part of the face, the neck and the upper part of the shoulder and chest on the left side. The patient had a slight fever (temperature 99.5 to 100.0 F.) for several days. The vesicles disappeared in about fourteen days,