BACKGROUND Primary care is expected to play a significant role in the management of patients with genetic problems. Currently, this particularly involves patients with a family history of cancer. If GPs are to exercise their gatekeeper role efficiently in this area, they must be able to evaluate genetic risk and make appropriate referral decisions. OBJECTIVE The aim of this study was to examine GPs' ability to assess risk and to make appropriate referral decisions for women with a family history of breast/ovarian cancer, and to determine their expectations of a referral to secondary care. METHODS A questionnaire survey was carried out of the 282 GP principals working within Bedfordshire Health Authority. GPs were asked to make decisions for six simulated cases of women presenting with a family history of breast or ovarian cancer. RESULTS A total of 164 (58%) GPs returned completed questionnaires. Across the six family histories, the percentage of GPs making an appropriate risk assessment ranged from 21% [95% confidence interval (CI) 14-27%] to 63% (95% CI 56-71%), and an appropriate referral decision ranged from 40% (95% CI 32-48%) to 80% (95% CI 73-86%). Regardless of their accuracy of risk assessment, most GPs were consistent in deciding not to refer low risk women and to refer moderate and high risk women (range 71-85% of GPs for the six family histories). Only 43 (26%, 95% CI 20-33%) of GPs knew the three most important criteria for risk assessment. CONCLUSIONS GPs require more help and education to enable them to perform their gatekeeper role satisfactorily when assessing patients with a family history of breast/ovarian cancer.