We present the findings of a pilot study to assess the perception of risk in 155 women with a family history of breast cancer by questionnaire. Only 11% of women were able to identify the correct population risk and more than half were unable to assess their own lifetime risk within 50% of the clinicians' estimate. Although it is probable that women are helped by genetic counselling and if at substantial risk, annual mammography, the psychological impact of assigning true risk and the value of mammography need to be evaluated.