The clinical significance of osteoporosis arises from the fractures that occur. Of these, the hip fracture in particular is associated with high morbidity, mortality and socio-economic costs. The primary goal of osteoporosis treatment is fracture prevention. In this chapter we try to answer the question of how to assess fracture risk and how to identify those above a given risk threshold so that treatment can be given to those in whom fractures can be prevented (cost-) effectively. At first, the two main strategies for fracture prevention--population screening and case finding--are discussed. Then a fracture risk assessment score, based on easily identifiable clinical risk factors, is proposed. This clinical risk factor analysis can guide the decisions whether additional bone assessment is relevant and whether treatment should be started. Finally, we advocate that absolute fracture risk is important for communication with the patient about the decision whether or not to initiate treatment.