Previous investigations with plain radiography, myelography, and computed tomography have shown that degenerative disease of the cervical spine frequently occurs in the absence of clinical symptoms. We studied the magnetic resonance-imaging scans of sixty-three volunteers who had no history of symptoms indicative of cervical disease. The scans were mixed randomly with thirty-seven scans of patients who had a symptomatic lesion of the cervical spine, and all of the scans were interpreted independently by three neuroradiologists. The scans were interpreted as demonstrating an abnormality in 19 per cent of the asymptomatic subjects: 14 per cent of those who were less than forty years old and 28 per cent of those who were older than forty. Of the subjects who were less than forty, 10 per cent had a herniated nucleus pulposus and 4 per cent had foraminal stenosis. Of the subjects who were older than forty, 5 per cent had a herniated nucleus pulposus; 3 per cent, bulging of the disc; and 20 per cent, foraminal stenosis. Narrowing of a disc space, degeneration of a disc, spurs, or compression of the cord were also recorded. The disc was degenerated or narrowed at one level or more in 25 per cent of the subjects who were less than forty years old and in almost 60 per cent of those who were older than forty. The prevalence of abnormal magnetic-resonance images of the cervical spine as related to age in asymptomatic individuals emphasizes the dangers of predicating operative decisions on diagnostic tests without precisely matching those findings with clinical signs and symptoms.