Over the past two decades, clinical and pathologic studies have examined the pathophysiology of the so-called acute coronary syndromes: unstable angina and non–Q wave and Q wave myocardial infarction. In patients with these conditions, atherosclerotic plaque rupture leads to a variable amount of platelet adhesion and aggregation, vasoconstriction, and partially or totally occlusive thrombus formation. Medical therapy to inhibit platelet aggregation and thrombus formation has proved to be effective in improving survival and preventing recurrent ischemia and infarction in patients with acute coronary syndromes. Nevertheless, a residual coronary arterial stenosis may lead to recurrent ischemia, infarction, or death. As a result, there has been considerable interest in routinely performing coronary angiography and prompt revascularization in patients with unstable angina, even though such a management strategy has not proven to be beneficial in reducing cardiac events. This article focuses on the role of a conservative (maximal medical therapy, with catheterization and revascularization reserved for those with spontaneous or provocable ischemia) management strategy for the patient with unstable angina.