[Platelets play pivotal role in the pathophysiology of unstable angina, acute myocardial infarction and in complications following percutaneous coronary intervention. Three classes of platelet-inhibiting drugs, aspirin, thienopyridines and platelet glycoprotein IIb/IIIa inhibitors are now commonly used for the prevention and treatment of the disorders of coronary artery thrombosis. For the last several decades, aspirin has been the sole option for antiplatelet therapy in the treatment and prevention of the manifestations of cardiovascular disease. However, a wider selection of antiplatelet agents, including the thienopyridines (ticlopidine and clopidogrel) and the platelet glycoprotein IIb/IIIa receptor antagonists are available today. This review summarizes these drugs and scientific data that have led to their use in primary and secundary prevention, unstable angina, myocardial infarction and percutaneous coronary intervention.]