Fifty-nine patients with end-stage renal disease undergoing long-term dialysis were studied prospectively for joint disease. Radiographic assessment allowed division of patients into 3 groups: group 1 included 12 patients with renal osteodystrophy and erosions of the metacarpophalangeal, proximal interphalangeal, distal interphalangeal, shoulder, wrist, and knee joints; group 2 had 11 patients with renal osteodystrophy without articular erosions; group 3 included 36 patients without osteodystrophy or erosions. Clinical manifestations were frequent in patients of group 1 and included episodes of arthralgias of the metacarpophalangeal, wrist, proximal interphalangeal, and knee joints. Patients of groups 1 and 2, particularly those of group 1, had a longer mean duration of dialysis and a higher mean serum alkaline phosphatase level compared with group 3 patients. The study indicates that there is a relatively high incidence (20%) of erosive arthropathy in dialysis patients. Renal osteodystrophy, more specifically, secondary hyperparathyroidism, and duration of dialysis are important factors in the development of this articular disorder.