The authors report six cases of encephalitis localised in the brain stem. This disease occurred frequently during 1975, with the following symptoms and signs: fever, paralysis of several cranial nerves, temporary mental disturbance and C.S.F. changes. Several patients required tracheotomy and aritificial respiration. All patients recovered without any recurrences. Viral studies were negative. The possibility of a Listeria infection cannot be entirely eliminated.