Objectives: Our purpose was to determine factors independently associated with cardiac rehabilitation referral, which are currently not well described at a national level. Background: Substantial numbers of eligible patients are not referred to cardiac rehabilitation at hospital discharge despite proven reductions in mortality and national guideline recommendations. Methods: We used data from the American Heart Association's Get With The Guidelines program, analyzing 72,817 patients discharged alive after a myocardial infarction, percutaneous coronary intervention, or coronary artery bypass graft surgery between January 2000 and September 2007 from 156 hospitals. We identified factors associated with cardiac rehabilitation referral at discharge and performed multivariable logistic regression, adjusted for clustering, to identify which factors were independently associated with cardiac rehabilitation referral. Results: Mean age was 64.1 ± 13.0 years, 68% were men, 79% were white, and 30% had diabetes, 66% hypertension, and 52% dyslipidemia; mean body mass index was 29.1 ± 6.3 kg/m2, and mean ejection fraction 49.0 ± 13.6%. All patients were admitted for coronary artery disease (CAD), with 71% admitted for myocardial infarction. Overall, only 40,974 (56%) were referred to cardiac rehabilitation at discharge, ranging from 53% for myocardial infarction to 58% for percutaneous coronary intervention and to 74% for coronary artery bypass graft patients. Older age, non-ST-segment elevation myocardial infarction, and the presence of most comorbidities were associated with decreased odds of cardiac rehabilitation referral. Conclusions: Despite strong evidence for benefit, only 56% of eligible CAD patients discharged from these hospitals were referred to cardiac rehabilitation. Increased physician awareness about the benefits of cardiac rehabilitation and initiatives to overcome barriers to referral are critical to improve the quality of care of patients with CAD. © 2009 American College of Cardiology Foundation.