Osteoporosis constitutes a major financial burden for society, which will increase in the near future owing to the ageing of the population. Women are the most common victims of involutional osteoporosis because of post-menopausal bone loss induced by oestrogenic deficit. Men are nevertheless not completely untouched by osteoporosis, however, compared to women, they are under less threat. Every effort should be made to curtail the financial burden on society and to improve the quality of life of sufferers. The first steps should be to increase the calcium intake, the level of exercise and to decrease the risk of falls. A preventive therapy with oestroprogestogens should be instituted at the time of the menopause, provided there is no contraindication. In the absence of fracture data, the modalities of alternative therapies like calcitonin and bisphosphonates are still debated. For people already suffering from fractures, restorative therapy should be considered. Sodium fluoride therapy is able to provoke a decrease in vertebral fracture frequency without compromising cortical bone strength provided elementary rules for its use are respected. Whether bisphosphonates can protect against fractures is still unsettled. Vitamin D has a physiological role, particularly in institutionalized elderly patients deprived of any exposure to the sun. Anabolic steroids are not devoid of side effects, and furthermore, no fracture data are so far available.