Although there is substantial evidence that cardiac rehabilitation is beneficial for post myocardial infarction (MI) patients, such programs are currently under utilized. This study examined systematic criteria predicting physician referral to and patients' participation in cardiac rehabilitation programs. Patients discharged for MI were interviewed in-hospital and at 6-12 weeks post discharge to determine referral, participation, and completion. Stepwise logistic regression analyzed factors associated with rehabilitation. Factors associated with referral to rehab were catheterization (p < 0.001), bypass surgery (p < 0.01), cardiologist/cardiac surgeon appointment (p < 0.02), and age (p < 0.01). Participation was increased for those with bypass surgery (p < 0.001), and referral to cardiologist or cardiac surgeon (p < 0.001). Type of provider significantly influences referral to and participation in cardiac rehabilitation. This suggests that encouragement plays a strong role in attendance for rehabilitation. The same strong encouragement should be given to the broader range of MI patients who stand to benefit from cardiac rehabilitation.