The IST, CAPRIE and ESPS-2 have shown that large collaborative randomised trials can be conducted in stroke medicine and can provide statistically and clinically significant results. They, and other concurrent studies, have highlighted the potential hazards of early anticoagulation, and the effectiveness and safety of early (and continuous) antiplatelet therapy in limiting early stroke recurrence and its consequences. In addition, they have shown that antiplatelet agents with differing mechanisms of action can have different effects, and perhaps additive effects when combined. The ESPRIT trial should delineate the roles of oral anticoagulant therapy, and the combination of aspirin and dipyridamole, in the prevention of stroke due to arterial disease. Future trials will hopefully determine the role in secondary stroke prevention of inhibitors of the platelet GPIIb/IIIa complex (the final common pathway of platelet aggregation), the combination of anitplatelet agents with different mechanisms of action (e.g. aspirin and clopidogrel, aspirin and IIb/IIIa inhibitors), the combination of antiplatelet agents and oral anticoagulants (which may simultaneously modify platelet function and fibrin production), and the combination of antithrombotic and cholesterol-lowering (statin) medications.