Aims: To compare the rates of employment, and advice offered concerning careers, in adults with congenital heart disease and controls. To assess the impact of the severity of the congenital cardiac malformation on the chances for employment. Methods: We solicited responses from 299 adults with congenitally malformed hearts, asking them to answer questions from a questionnaire posed at interview by a trained nurse. The adults were asked to give an identical questionnaire to a friend to act as a control. We received responses from 177 of the controls. Results: The responses showed that 51 of 156 (33 per cent) adults with congenital heart disease were unemployed, and 37 of 151 (25 per cent) had been unemployed for more than a year. This is significantly more than 25 of 156 (16 per cent) matched controls unemployed, and 5 of 151 (3 per cent) controls unemployed for more than a year. Almost one-fifth of the adults with congenital heart disease (19 per cent) had received advice regarding their career which they found helpful, which is significantly fewer than the 31 per cent of controls. More (42 per cent) had been given advice against certain occupations than controls (11 per cent). Receiving career advice was significantly associated with employment in the population with congenitally malformed hearts, with almost three-quarters (73 per cent) of those given advice being employed compared to 46 per cent of those not given advice. This pattern was not seen in controls. The severity of the congenital cardiac malformation did not significantly affect the rates of unemployment. Conclusions: Whatever the severity of their disease, adults with congenitally malformed hearts are more likely to be unemployed than matched controls. They are less likely to receive useful advice regarding potential careers, and find the advice given less helpful, than controls, although receiving suitable advice is associated with being employed in the population with congenital cardiac disease.