Approximately 50% of women over the age of 50 are affected by osteoporosis #8211; the excessive thinning of bone. Traditionally, a number of different classes of antiresorptives have been used to treat it #8211; typically bisphosphonates, as well as selective oestrogen reuptuke modulators and calcitonin. Recently, a novel dual-action drug that acts as both a resorptive and an anabolic has become available, as well as true anabolic therapies which induce new bone formation. The development of convenient administration regimes has also been a key advance in increasing compliance and clinical improvements. In addition, research into basic cell biology has thrown up new targets that are now being exploited in R&D programmes, and may result in several new classes of therapy.