The risk of stroke increases with age, and hence the disease particularly affects the elderly, who are also at high risk for coronary heart disease. Epidemiological and observational studies have not shown a clear association between cholesterol concentrations and all causes of stroke. Large, long-term statin trials in patients with established or high risk for coronary heart disease have shown that statins decrease stroke incidence. These statin trials in a combined total of 70020 patients indicate relative and absolute risk reductions for stroke of 21% and 0·9%, respectively. By comparison, the number of strokes prevented per 1000 patients treated for 5 years in patients with coronary heart disease is nine for statins versus 17·3 for antiplatelet drugs and 17 for antihypertensive drugs. Although the Heart Protection Study showed that statins lower the risk of major coronary events in patients with a previous stroke, statins may not lower stroke recurrence in these patients. In this review, we discuss the potential reasons for the effects of statins on stroke and the mechanisms of action. Treatment strategies on the basis of global cardiovascular risk may be most effective. Additional studies in patients representative of the typical stroke population are needed.