The incidence of low back disability in workers was studied. Data was collected for 237 subjects aged 62 to 65, for whom work and medical records were available, including complete clinical, X-ray, and laboratory evaluations. Of these subjects, 56 percent had experienced severe low back pain and 44 percent had no record of medical treatment for low back pain. In subjects who had received medical treatment, 69 percent had degenerated intervertebral discs, 58 percent had osteoarthritis, and 28 percent had abnormalities of the unilateral ankle reflex. Of those who had received no treatment, the corresponding percentages were 19, 41, and 1. There were no significant differences between workers with strenuous or desk jobs in the incidence of disc degeneration, but workers with strenuous jobs received more medical treatment for back pain than desk workers. The author concludes that efforts to manage the low back problem in industry must be directed at minimizing disability by workplace and job design, patient education, and regular careful followup, exercise programs and rehabilitation of the patient.