When I gave a presentation on return to work after heart valve replacement at the Tenth Congress of the German Society for Thoracic and Cardiovascular Surgery in 1981, I was surprised by the relatively low level of interest that cardiac surgeons seemed to have in this subject. This stimulated me to intensify my research in this area and to extend it to patients with coron­ ary heart disease. Obviously, physiological and mechanical aspects of medical treatment are of special interest to the surgeon. For the majority of cardiac surgical patients, that is those with coronary heart disease, the technical problems of the operative procedure have been solved to a great extent. Many studies have demonstrated that, aside from reduction of symptoms, aortocoronary bypass operation can lead to improvement of cardiac performance un­ der stress conditions. However in spite of the technical solutions to hemodynamic problems, it has become very clear that the reintegration of patients into their social sphere has not been accomplished to the extent that might be expected, as exempli­ fied by the relatively low rate of postoperative return to work.