Psychological adjustment in 90 women (30 carriers and 60 non-carriers) who had undergone genetic testing for mutations in BRCA1 and BRCA2 breast/ovarian cancer susceptibility genes was compared with that of 53 women who were not offered genetic testing. Women were assessed prior to genetic testing and 7-10 days, 4 and 12 months after carrier status disclosure using self-administered questionnaires. Compared with women not offered testing, mutation carriers had significantly higher breast cancer distress 7-10 days (t=2.80, P=0.005) and 12 months (t=2.01, P=0.045) post-notification. Non-carriers showed a significant decrease in state anxiety 7-10 days post-notification (t=2.27, P=0.024) and in depression 4 months post-notification (t=2.26, P=0.024), compared with women not offered testing. These data show that non-carriers derive psychological benefits from genetic testing. Women testing positive may anticipate a sustained increase in breast cancer distress following disclosure, although no other adverse psychological outcomes were observed in this group.