Osteoporosis is caused by a reduction in bone mass, but the cause of osteoporotic fractures is multifactorial because fractures arise following various degrees of trauma. There are therefore several different categories of risk factors for osteoporotic fracture. They may be related to the determinants of bone mineral density, capture the risk of falls, be related to skeletal fragility independently of bone mineral density or a combination of these. The identification of strong risk factors permits the identification of patients in whom further assessment and treatment can be offered in case finding strategies.