Despite the inconsistent or weak association between cholesterol and stroke, lowering of cholesterol concentrations with statins reduces the risk of stroke in high-risk populations and in patients with non-cardioembolic stroke or transient ischaemic attack. Statin therapy is the most important advance in stroke prevention since the introduction of aspirin and antihypertensive treatments. Meta-analysis of randomised trials of statins in combination with other preventive strategies, including 165 792 individuals, shows that each 1 mmol/L (39 mg/dL) decrease in LDL cholesterol equates to a reduction in relative risk for stroke of 21.1% (95% CI 6.3-33.5, p=0.009). In secondary prevention of non-cardioembolic stroke, intense reduction of LDL cholesterol by statins also significantly reduced the risk of recurrent stroke (relative risk 0.84, 0.71-0.99, p=0.03) and major cardiovascular events (0.80, 0.69-0.92, p=0.002). Future directions include assessment of a target LDL cholesterol concentration of less than 1.8 mmol/L (70 mg/dL), the effects of triglyceride-lowering therapy alone or in combination with statins, and the effects of treatments to raise HDL cholesterol concentrations.