Osteogenesis imperfecta describes a group of heritable disorders characterized by excessive bony fragility and reduced skeletal mass. It is classified in terms of its clinical manifestations, but our understanding of the underlying genetic defects in collagen synthesis is increasing rapidly. The nonoperative and surgical orthopedic approaches to osteogenesis imperfecta aim at the maximum preservation of limb strength and the correction of deformities. Various pharmacologic agents have been administered to patients with osteogenesis imperfecta, but to date, none have proved effective in controlled trials. Prenatal diagnosis has been attempted and seems certain to assume greater importance as knowledge of the molecular genetic basis of the disease increases.