IN 1866 Sir William Broadbent described a case of "herpetic eruption in the course of branches of the brachial plexus, followed by partial paralysis in corresponding motor nerves." Since his original communication, several accounts of motor weakness accompanying herpes zoster have appeared, including the excellent review by Taterka and O'Sullivan in 1943. Generally, motor manifestations are confined to segments corresponding to the dermatomes in which the cutaneous lesions appear. It is believed that they result from an involvement of the anterior horn cells. To our knowledge, herpetic paralysis of the diaphragm has been reported only once previously. Our case is presented not only because of its rarity but also to emphasize the motor phenomena which may accompany some herpes zoster infections. Report of a Case A 60-year-old Puerto Rican woman was seen as an outpatient on July 18, 1960, because of severe superficial pain over the left shoulder, neck, and