Vestibular larobatory tests are not general necessary in the diagnosis of patients with a clear description of vertigo accompanied by positive otoneurological examination findings. The purpose of the study was to inverstigate the role of conventional vestibular laboratory tests in the diagnosis of patients compaining of hnonspecific vertigo, despite their having a documented normal otoneurological examination. The results patients referred for ambulatory vestibular laroratory testes due to a nonspecific illusion of movement, but with nornal otoneurological examination, were reviewed. Abnormalities were found in the vestibular tests of 35 patients (67 per cent), 22 of whom (63 per cent) were finally diagnosed as having a unilateral perpheral vestibular lesion, and 13(37 per cent) benign positional vertigo. These results suggests that a high percentage of patients with nonspecific vertigo and a normal otoneurologica examination probably suffer from peripheral vestibular dusfunction, which can be objectively documented by the ENG and SHA tests.