Atherosclerotic disease is one of the major causes of premature death. In patients with atherosclerotic disease, antiplatelet therapy with aspirin has been shown to decrease the risk of subsequent events by about 20%. In one large randomized controlled study, clopidogrel showed a marginal benefit over aspirin in the prevention of ischaemic vascular events in high-risk patients. Clopidogrel is therefore an alternative in secondary prevention for those patients who are unable to tolerate aspirin. A literature search was performed using MEDLINE, EMBASE, and the Cochrane library, using the keyword 'clopidogrel'. One published randomized, controlled trial was found which evaluated the effects of clopidogrel in the prevention of vascular ischaemic events.