A review of the empirical findings linking vestibular response abnormalities to psychopathology, and particularly to schizophrenia, indicates that these data do not unequivocally document the presence of peripheral or central disease of the vestibular system in any patient group. The reasons for this ambiguity include: use of imprecise stimulation techniques, inaccurate measures of responsiveness, unreliable measures of quantification, and the absence of experimental control over extravestibular variables. Future directions for research in this area are discussed, including the localizing information derived from properly conducted tests of the vestibulo-ocular reflex in studies of oculomotor function.