The role of HRT for the prevention of osteoporosis has been clarified by the recent results of the WHI. There is consistent and favorable data from RCTs supporting the efficacy of HRT on the surrogate outcome of bone density at both cortical and trabecular sites, including a dose-response relationship. Both observational and RCT data provide support that HRT has a positive impact on the reduction of vertebral and hip fractures. The unfavorable risk/benefit profile of HRT, however, strongly limits its use for prevention of osteoporosis, given that there are other medications that have demonstrated fracture efficacy.