The prolonged depression of myocardial function following episodes of myocardial ischemia now known as myocardial stunning, appears ubiquitous in both the experimental and clinical settings. With recent therapies designed to ameliorate ischemic myocardium, e.g., coronary artery bypass, coronary thrombolysis, coronary angioplasty, the inexorable progression from ischemia to necrosis has been averted more successfully and frequently, which permits appearance of myocardial stunning to become clearer. Myocardial stunning occurs in the presence of a multitude of inciting stimuli to myocardial ischemia, including a fixed stenosis, relief from stenosis or even in the presence of reduced coronary reserve, without a coronary stenosis. It will be potentially most interesting to determine if myocardial stunning also belies the hibernating myocardium and is, in fact, its actual mechanism.