Hip fracture incidence accelerates approximately 10 years following the menopause in women and after age 70 in men. Approximately one million Americans suffer fragility fractures each year at a cost of over 14 billion dollars. The disability, mortality and cost of hip and vertebral fractures are substantial in the rapidly growing aging population so that prevention of osteoporosis is a major public health concern. Bone mineral density (BMD) measurement is used to make the diagnosis of osteoporosis prior to incident fracture, and to predict fracture risk. Recommendations for treatment and prevention of osteoporosis based on bone mineral density score published by the World Health Organization and the National Osteoporosis Foundation are outlined.