The detailed study of a battery plate maker, who had worked with cadmium for 36 years, showed that proteinuria, typical of renal tubular dysfunction, had been observed for 25 years and during the last 12 years of his life the patient had suffered increasing disability from gross bone disease. Several bone biopsies and detailed metabolic studies showed typical severe osteomalacia, which responded well initially to calcium and vitamin D treatment. Examination of the liver both in life and after death showed a gross excess of cadmium. This was also found in the kidneys after death. Previously unreported changes were present in the bones, especially the lumbar vertebrae which were probably more the result of gross bone deformity than cadmium deposition. The mechanism of development of the severe acquired Fanconi syndrome was thought to be a combination of dietary calcium and vitamin D deficiency and impaired calcium absorption from abnormal vitamin D synthesis, related to the cadmium deposition in the renal tubules, which also caused the defect in renal tubular reabsorption.