As genetic testing for susceptibility to breast cancer becomes more widespread, alternative methods for educating individuals prior to testing will be needed. Our objective was to compare face-to-face education and counseling by a genetic counselor with education by an interactive computer program, assessing the effects of each on knowledge of breast cancer genetics and intent to undergo genetic testing. We used a randomized, controlled trial. Seventy-two self-referred women with a first-degree relative with breast cancer received outpatient education and counseling at the Clinical Center of the National Institutes of Health (NIH). Twenty-nine received individualized counseling from a genetic counselor (counseling group), 29 received education from an interactive computer program followed by individualized counseling (computer group), and 14 were controls. Both pre- and postintervention assessment of knowledge about breast cancer genetics and intent to undergo genetic testing were measured. The control group participants correctly answered 74% of the knowledge questions; the counselor group, 92%; and the computer group, 96% (P < .0001). Unadjusted mean knowledge scores were significantly higher in the computer group than the counselor group (P = .048), but they were equivalent when adjusted for demographic differences (P = 0.34). Intent to undergo genetic testing was influenced by the interventions: preintervention, a majority in all groups (69%) indicated that they were likely (definitely and most likely) to undergo testing; after either intervention coupled with counseling, only 44% indicated that they were likely to do so (P = .0002; odds ratio = 2.8, 95% CI = 1.7–4.9). We concluded that a computer program can successfully educate patients about breast cancer susceptibility, and, along with genetic counseling, can influence patients' intentions to undergo genetic testing. © 2001 Wiley-Liss, Inc.