Factors influencing the effect on employment status were investigated in 250 patients (males: females 224:26) who underwent coronary artery bypass surgery between March 1983 and November 1985. The median age at operation was 57.9 (range 36.6-69.4) years and the median follow-up time 32 (19-52) months. Preoperatively 149 patients (59.6%) were receiving sick pay or disability pension because of their heart disease. Only 64 (25.6%) were gainfully employed, in contrast to 97 (38.8%) at follow-up. Of those who were working at the time of operation, all but eight returned to work postoperatively. At follow-up 183 (80.3%) were free from symptoms or much improved, with degree of improvement somewhat greater in those who were working postoperatively. The period of sick leave and the preoperative waiting time were significantly shorter for patients who were working postoperatively than for those who were awarded disability pension. Age, previous myocardial infarction, duration of preoperative angina and type of work were also found to influence postoperative employment status.