Objective: To determine the effect of bone density information on a woman's decision about hormone replacement therapy (HRT). Methods: One hundred forty women were assigned randomly to receive either educational information about osteoporosis and a voucher for a bone mineral density test 12 months later or the same educational information plus an immediate dual-energy x-ray absorptiometry test for bone mineral density. Women in both groups were offered prescriptions for HRT. Results: Of the 93 women who received a bone mineral density test, 63.4% elected HRT and filled their prescription, compared with only 20.0% of the 43 women who did not have a bone mineral density test (P < .01). Women who were classified as osteopenic (between −1 and −2.5 standard deviations [SDs] of the young normal bone mineral density) or osteoporotic (more than 2.5 SDs below young normals) were more likely to choose HRT (69.4%) than were women whose bone mineral density was in the normal range (51.6%) (above −1 SD of the young normal bone mineral density value). Conclusions: A bone mineral density test, regardless of the result, had a significant effect on women's decisions to accept HRT. Within the group having the test, women with lower bone mineral density were more likely to choose HRT.