Although much attention has been given to measuring the risks associated with menopausal hormone therapy (HT), decisions about HT should be guided largely by individual patient preferences and values. Because the magnitude of the risks associated with HT for healthy 50-year-old women are exceedingly small (typically <1 in 1000) and its impact on survival are negligible, patient preferences and values become the most critical considerations. To make a rational and informed decision about HT, a woman needs to weigh any short-term gains in quality of life from HT against its longer term risks. To do this, clinicians need to gauge the patient's risks for the conditions affected by HT, the effects of HT on these risks, understand the woman's menopausal symptoms and identify the best treatment. This can be time consuming and challenging for clinicians to perform, and appears to be rarely done in clinical practice. Decision support tools can more rationally use available resources by shifting responsibilities away from those least able to perform them towards those most appropriate to perform them. The Internet presents new opportunities for delivering and disseminating individualized decision support tools that can help with menopausal counseling. A web-based decision support tool, Women's Interactive System about Decision On Menopause (WISDOM), was designed to improve the quality of treatment decisions around menopause and HT by providing individualized information about the impact of menopausal treatments on symptoms and risks. Preliminary trial results suggest a positive impact on clinicians and patients. The unique challenges and opportunities in developing and testing web-based decision support tools are discussed.