The therapy of unstable angina has changed consider ably in the last 15 years. An improved understanding of the pathophysiology has led to many of the changes. Thrombus, platelet activation, progression of athero sclerosis, and coronary vasospasm all appear to have a role. Initial management in unstable angina should begin with aggressive medical therapy with nitrates, calcium antagonists, beta blockers, and aspirin. In patients who are refractory to aggressive medical management, early cardiac catheterization and coronary arteriography is in dicated. The literature appears to confirm that patients with unstable angina who are stabilized with aggressive medical therapy fare as well as those treated with emer gency bypass surgery. Percutaneous transluminal coro nary angioplasty (PTCA) is the treatment of choice in medically refractory unstable angina patients with single-vessel coronary disease. New approaches include culprit lesion angioplasty, thrombolytic therapy, coronary sinus retroperfusion, and new catheter-based revascularization methods such as intracoronary stents, laser methods and atherectomy. Culprit lesion angioplasty involves angioplasty of only the angina-producing artery in patients with multivessel coronary disease. Early data suggest that this may be an effective short-term alternative to multivessel PTCA or bypass surgery. Recent data also suggest a beneficial role for thrombolytic therapy and synchronized coronary si nus retroperfusion with arterial blood in patients with unstable angina. New catheter-based approaches are in the early stages of development, and their eventual role in the treatment of coronary artery disease and unstable angina remains to be elucidated.