This study was undertaken to determine the incidence of spontaneous nystagmus (SN) in normals and evaluate its significance in patients. There were 60 normal subjects and SN was recorded in 8 (13%). Between January 1979 and November 1981, SN without past pointing was the only detectable abnormality in 41 patients undergoing a vestibular evaluation. An intracranial lesion could be confirmed in 34 patients (83%). These results from both normal subjects and patients are compared with earlier reports in the literature. Because of differences in nomenclature and classification of SN and differences in technique of searching and recording SN, no true comparisons are possible. Our conclusion is that SN in normals should be regarded as an oculomotor abnormality for which there is no detectable cause. In patients SN is a valuable diagnostic sign and should be considered significant regardless of its slow phase velocity.