The discovery that genetic factors are involved in the aetiology of colorectal cancer, has prompted many relatives of affected individuals to seek genetic counselling and screening. This paper describes the demand for genetic services by families with colorectal cancer in south-east Scotland, their expectations and views of the service offered. The annual referral rate over the 21-month study period, for patients with a family history of colorectal cancer, was 0.11 per 1000 patients on general practitioner lists. This is one third of the rate for patients with a family history of breast cancer and in comparison with the breast cancer group, relatives of colorectal cancer patients were significantly older and less socially deprived. Approximately one third were referred via a hospital specialist unit. One hundred patients were included in the study. Mean (+/- standard deviation) age was 43 (+/- 10.7 years), 75 were female and 31 were self referrals. Before the consultation, almost half the patients had an inflated perception of their risk and there was little change at follow-up. There was an improvement in objective understanding after counselling which was sustained up to 6 months but only two thirds remembered their objective risk accurately. Most patients were satisfied with the consultation. Our findings suggest the need to educate individuals, in particular men, younger people and the more socially deprived, about the relevance of a family history of colorectal cancer and to facilitate patients' comprehension of their risk status.