The Kaessmann compression device was employed in 26 patients with fractures of the long bones. In 15 fractures of the tibia, prompt healing occurred, even in fractures in the distal one-fourth of the tibia. Most of these cases were treated without external plaster support, and were permitted early ambulation, with partial weight-bearing. The technique for immobilizing these fractures involves a sliding a Kuntscher nail over a tension rod, and then fixing the clevis of the tension rod to the distal bone fragments by a transverse screw. The Kuntscher nail is fixed to the proximal bone fragment by a metal lip, and after compression is achieved, a locking sleeve fixed by a screw to the tension rod, prevents loss of compression. In 11 cases of pseudarthrosis of the tibia, the medullary canal was enlarged by passing graduated drills down the bony canal, over a guide wire. The compression rod was then inserted across the pseudarthrosis, and seventy to 80 kg/cm2 pressure was applied to the bone ends. No bone grafting procedure was performed. In all 11 cases, prompt union occurred. Postoperative management was similar to that employed in the treatment of fresh fractures. Three success fusions of the ankle also attest to the effectiveness of this immobilization. Although controversy exists regarding the role of compression in the healing of fractures, the axial compression rod does overcome distraction, compresses the bony surfaces, immobilizing them securely to produce union with an economy of callus.