Physical examination, bone densitometry and x-ray are the mainstay in the evaluation of osteoporosis. A limited number of simple blood tests are sufficient to discriminate most secondary forms of osteoporosis and to exclude osteomalacia. Bone-specific biochemical markers play an increasing role in monitoring osteoporosis therapy. They may also play a role in treatment decision in the coming years. Bone biopsies are helpful if findings are unclear or inconsistent. The present review gives a summary of the opportunities and limitations of the above diagnostic procedures.