The aim in the prevention and treatment of osteoporosis is to prevent fractures.In prevention of osteoporosis on the population level it is essential to ensure sufficient intake of calcium and vitamin D and to advise proper exercise habits as well as cessation of smoking. Diagnosis of osteoporosis is the responsibility of primary care. Bone density measurements should be targeted at risk groups (see table ). General, non-targeted DXA-screening is not indicated . Bone density measurements targeted at persons with increased risk are cost-effective and should be a part of the public health care. The treatment yields most benefit for those patients who already have a history of a low energy fracture, usually after a fall on flat ground. Patients who have experienced such a fracture should be referred to bone density measurement or directly to treatment. They have a 2-4-fold risk of refracture. Causes of secondary osteoporosis should be identified and treated accordingly (e.g. hyperparathyroidism, hyperthyroidism, Cushing's syndrome, hypogonadism, uraemia, coeliac disease, myeloma, glucocorticoid therapy, rheumatoid arthritis). Bisphosphonates are the first line drugs in the treatment and prevention. Oestrogen therapy is suitable also in the prevention and treatment of osteoporosis in women who have postmenopausal symptoms that require treatment and who have no arterial disease. The success of pharmacological treatment is assessed by bone density measurements and, on the population level, by the decrease in complications.