The choice of dosing of osteoporosis drugs should lie upon appropriate studies, indicating particularly the minimal efficient dosing which is, in this area, of a particular importance. Because of technical difficulties in the realisation, very few studies have been reported at the present time. From a practical point of view, the good choice of dosing of anti osteoporotic drugs must be studied from dose-response relationship curvus at the beginning of phase III clinical studies. From literature, it appears that the supposed optimal dosing of anti osteoporotic drugs have frequently been assessed empirically or from studies with patent methodological errors. Such studies should be on the contrary, prospective in parallel groups, randomized, double-blinded, using a pertinent, validated and more sensitive criteria of response.