Sodium fluoride has clearly been shown to have pronounced effects on the skeleton, probably more than any other currently available therapeutic agent. Unfortunately, these effects appear to be both beneficial and potentially toxic at the same time. A more clear understanding is needed of the basic mechanisms whereby these effects (both beneficial and detrimental) are exerted. When such data are forthcoming, it may be possible to modify the therapeutic use of fluoride in osteoporosis and other brittle bone diseases such that the beneficial effects outweigh the toxic effects much more completely than is currently the case. Until such time, and despite thirty years of meaningful clinical investigation, we must conclude that sodium fluoride has no role in clinical medicine outside the confines of properly conducted clinical research studies.