In a retrospective review of thirty-two patients with hereditary multiple exostoses, anthropometric data were plotted and the nature and extent of the associated deformities were noted. Although such patients tend to be short, true dwarfism is rare. Mild skeletal disproportion occurs since limb involvement is greater than spinal involvement. The position and relative frequency of exostoses at the metaphyseal regions of the long bones were documented. In the upper extremity, 60 per cent of the patients had moderate to severe involvement of the forearm. The distal end of the ulna always was more seriously affected than the radius. Dislocation of the radial head occurred in 22 per cent of the elbows that were assessed. Moderate to severe rotational limitation was found in 33 per cent of the forearms. In the lower extremity, coxa valga (25 per cent) and occasionally femora vara were seen, but these deformities were rarely of clinical significance. When genu valgum occurred, the valgus deformity was within the tibia itself. Valgus deviation of S degrees or greater(mean deviation, 10 degrees) was found in 33 per cent of the tibiae assessed, and 20 per cent of the patients required an osteotomy at the proximal end of the tibia to correct the deformity. Obliquity of the distal tibial epiphyseal surface was seen frequently, and 54 per cent of the ankles assessed were markedly abnormal. The relative shortness of the fibula in relation to the tibia and the abnormally proximal position of the lateral malleolus in relation to the medial malleolus were documented. Limb-length discrepancies were common. In 50 per cent of the patients, the discrepancy was great enough to warrant operative epiphyseal arrest, although this was done in only 23 per cent. Operations were performed frequently, with an average of 2.7 procedures per patient. The procedures involved removal of the exostoses, epiphyseal arrest, excision of the radial head, and corrective osteotomy.