There has been much discussion over the years about the effects of hormone replacement therapy (HRT) on cardiovascular disease. Results have recently been published from the WISDOM trial, a multicentre, randomised, placebo-controlled, double-blind trial recruiting from primary care centres in the UK, Australia and New Zealand. The trial was stopped early following adverse cardiovascular outcomes in the HRT arm of the American Women's Health Initiative (WHI) trial. By this time the WISDOM trial had screened more than 56,000 postmenopausal women aged 50-69 years (mean age 63), and 5,692 had started treatment. Although WISDOM never reached its full potential, its message is broadly similar to the WHI trial: HRT increases cardiovascular and thromboembolic risk when started in older postmenopausal women. [With external links to current evidence and summaries]