The presence of directional preponderance in the peripheral and central vestibular disorders and the relation of its phenomenon to the definitive etiological factors, spontaneous nystagmus, positional nystagmus and the role of lateralization of directional preponderance were described. Directional preponderance is helpful to distinguish between peripheral and central lesions. The direction of this phenomenon is significant in the supratentorial CNS disturbances. In the peripheral lesions it is possible to estimate the progression of the disease. The coexistence of the directional preponderance, spontaneous nystagmus and positional nystagmus has the diagnostic value in neurootology.