One in three women and at least one in 12 men in the UK have osteoporosis, a condition which can lead to fractures, deformity, pain and disability, at a cost to the NHS of around £1.5 billion each year.1,2 Bisphosphonates offer a therapeutic option for preventing and treating osteoporosis. Here, we assess and compare the three bisphosphonates (alendronate, etidronate and &#9660risedronate*) licensed for such use in the UK. We do not consider the four bisphosphonates (clodronate, pamidronate, tiludronate and &#9660zoledronate) that are licensed in the UK only for the treatment of Paget's disease of bone and/or hypercalcaemia of malignancy.