Tinnitus is a frequent and annoying accompaniment of occupational hearing loss. Detailed case histories of 2,442 workers claiming compensation for hearing impairment were analyzed with respect to the incidence and characteristics of tinnitus. It was present in 58% of claimants, and was rated as a major problem in 19%. It was usually bilateral, and there was no evidence of ear differences in incidence or severity. Most commonly, it was tonal and of high pitch. There was no apparent relationship of tinnitus incidence to hearing loss severity, but the data suggest a higher incidence in workers exposed to impulse noise.