Patients with an acute unilateral peripheral vestibular loss present with severe vertigo, nausea, and vomiting. The diagnosis rests on finding spontaneous nystagmus (horizontal/torsional, unidirectional), gait imbalance (falling toward the side of lesion) and a positive head thrust sign (corrective saccades after head thrusts toward the lesion side). When no associated auditory or neurological symptoms and signs are present, the disorder usually results from viral or postviral inflammation of the vestibular nerve (vestibular neuritis). Recent studies suggest that early treatment with high-dose steroids improves the outcome with vestibular neuritis, but the risk/benefit of such treatment has not been adequately assessed. Most patients return to normal even if there is permanent unilateral peripheral vestibular loss. Patients with bilateral symmetrical peripheral vestibular loss do not have vertigo or spontaneous nystagmus but rather complain of imbalance and oscillopsia. They have a positive head thrust sign in both directions and have decreased visual acuity with head shaking. Most causes of bilateral peripheral vestibular loss are associated with bilateral hearing loss, although some ototoxic drugs, such as gentamicin, are remarkably selective for vestibular damage. Treatment is directed at prevention when possible and vestibular rehabilitation to help the patient compensate for the vestibular loss.