The aim of this paper is to review the benefice of various antiosteoporotic treatment (calcium and vitamin D, raloxifene, bisphosphonates, calcitonin, PTH, strontium ranelate) and to discuss for which women with osteoporosis these treatments are efficient. The age, previous fractures, and bone mass measurement (T-score) identify women at high risk for subsequent fracture. The development of assessment tools for predicting fracture risk, the use of the NNT (number needed to treat), and economical analyses including QALY (quality-adjusted life-year) are particularly helpful. Economical analyses take into account the health care resources needed to get these benefits. At 50 years, only calcium and vitamin D are cost-effective, whereas at 70 years, bisphosphonates and raloxifene are also cost-effective.