In a prospective study of 1507 patients, evaluated consecutively for facial palsy in the Cranial Nerve Research Clinic at the Kaiser Permanente Medical Center, Oakland, California, between 1966 and 1976, 185 cases (12%) were diagnosed as Ramsay Hunt syndrome. In 46 cases (25%), the diagnosis of herpes zoster was confirmed by acute and convalescent serum titers for varicella-zoster virus. In 139 cases (75%), viral titers were not performed and the diagnosis was based on the characteristic clinical presentation of the Ramsay Hunt syndrome. The data were subjected to multivariate analysis evaluating age, sex, race, signs, and symptoms at onset, severity of paralysis, associated medical problems with concomitant neurologic deficits, and response to therapy. These were compared with data of 1202 patients with Bell's (herpes simplex) palsy. The facial palsy of Ramsay Hunt syndrome was found to be more severe, to cause late neural denervation, and to have a less favorable recovery profile than Bell's (herpes simplex) facial palsy. Prognostic factors and treatment recommendations are discussed.