A decade ago, physicians and scientists were excited about emerging research on estrogens and brain function. The translational implications at the time were that estrogen-containing hormone therapy (HT) might be good for the brain, and might be especially good for improving memory and for preventing and treating Alzheimer disease. Basic and clinical scientists, spurred by the therapeutic possibilities, have continued to study these issues. Are health care providers now in a better position to advise their female patients on the cognitive consequences of HT? This article reviews data relevant to this question and analyzes the risks.