Osteoporosis is a generalized disease of bone that increases the fracture risk. Among the multiple factors involved in osteoporosis, some, but not all, are related to bone mass. To decrease osteoporotic fractures, we must be able to identify those patients who require preventive management. Bone mineral density (BMD) measurement by dual-energy X-ray absorptiometry is currently the method of reference for evaluating the fracture risk and deciding whether treatment is in order. Although BMD measurement is specific for detecting high-risk individuals, it misses a notable proportion of individuals who have clinical or epidemiological risk factors for osteoporosis. Therefore, composite scores that rely both on BMD and on validated clinical risk factors have been developed. FRAX™, a tool developed under the aegis of the World Health Organization, was designed to predict the 10-year probabilities of sustaining a major osteoporotic fractures or a hip fracture. The cutoff value beyond which treatment should be initiated needs to be determined, based not only on clinical criteria, but also on economic considerations.