The clinical attraction of being able to measure bone density in a precise and accurate manner is clear. With this information, clinicians can identify osteopenic postmenopausal women, assess the effects of disease on the skeleton, and examine the effect of therapy. Significant advances have been made in the last decade in methodology of bone-mass measurements, leading to a number of safe, precise, and accurate techniques. The field continues to change and, for example, dual photon absorptiometry, which itself was a major advance, has now effectively been superceded by dual energy X-ray absorptiometry. It is predicted that such methodology will continue to find an expanding role and will soon be considered part of routine clinical practice. A brief review of the various methodologies that have commonly been used for bone-mass measurements is presented.