Platelet GPIIb/IIIa receptor antagonists have been shown to be more potent than aspirin in inhibiting platelet function in vitro and decreasing thrombotic vascular events in animal models in vivo. One of these agents (c7E3 Fab, abciximab, ReoPro) significantly decreased the ischemic complications of percutaneous coronary interventions when given in conjunction with aspirin and heparin to patients at high risk of such complications, and other agents (Integrelin and tirofiban) have shown favorable trends. This review focuses on what we have learned from studies of patients treated with c7E3 Fab, including its pharmacology, its potential mechanism(s) of action, the ability to reverse its effects with platelet transfusion, and the risks of hemorrhage, thrombocytopenia, reinjection, and performing coronary artery bypass surgery. The future of GPIIb/IIIa antagonists therapy is considered, including the potential of orally active agents.