There is insufficient knowledge about secondary prevention after coronary artery bypass grafting (CABG). Most of it is gathered from patients suffering from myocardial infarction and angina pectoris, only a minority of whom have undergone CABG. Whereas it seems clear that these patients should give up smoking and reduce low‐density lipoprotein (LDL) cholesterol, there is uncertainty about the optimal antiplatelet regimen and antithrombotic treatment. There are some data indicating the benefit of behaviour modification. There is room for improvement and more knowledge when it comes to secondary prevention after CABG.