Percutaneous coronary intervention produces vessel wall injury and activation of platelets that are responsible for producing peri-procedural ischemic complications. The importance of adequate antiplatelet therapy during coronary intervention to reduce platelet mediated ischaemic complications has been recognized for some time. Until recently, adjunctive treatment with aspirin was the only available antiplatelet therapy after coronary intervention that had demonstrated benefit. During the last decade, newer and more potent agents have demonstrated consistent reductions in ischaemic events after intervention and appear to have some enduring effect. Additionally, optimization of antiplatelet therapy with aspirin and the thienopyridines after coronary stenting has been an important advance allowing for the current liberal use of coronary stents.