We aimed to prospectively evaluate the efficacy of a multi-modal surveillance programme for the early detection of familial breast cancer. Ultrasound, mammography and breast magnetic resonance imaging were evaluated in 413 women who participated in a prospective study with a median follow-up of 2.2 years (range 1-6.75 years). Of these, 49 women carried a BRCA mutation, 203 were at high and 161 at moderate risk. Breast carcinomas diagnosed within the programme were compared with 297 carcinomas previously observed in the risk group and 7894 carcinomas documented in the regional cancer registry within the same time period. Overall, 41 breast carcinomas and no interval carcinoma were detected. The detection rates averaged 107.2/1000 for mutation carriers with highest rates between 20 and 39 years of age, 45.8/1000 for high-risk women with highest rates between 40 and 49 years of age and 23.9/1000 for moderate-risk women with highest rates between 50 and 74 years of age. Overall, 82.8% of the breast carcinomas were node negative and 85.4% pre-invasive or smaller than 2 cm. In comparison, of breast carcinomas detected outside the programme only 47.8% were node negative (P=0.0005) and 43.8% pre-invasive or smaller than 2 cm (P<0.000 01). Of those gathered in the local cancer registry 55.7% were node negative (P=0.004) and 47.6% pre-invasive or smaller than 2 cm (P<0.000 01). Our data indicate that (1) there is a strong correlation between breast cancer detection rates, risk status and age at disease onset and (2) a multi-modal surveillance programme can detect early-stage hereditary breast carcinomas.