Objective: The preventive effect of 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) on progression of carotid intima-media complex thickness (IMT) has been shown exclusively in nonstroke Western patients. The Japan Statin Treatment Against Recurrent Stroke (J-STARS) Echo Study aims to determine the effect of pravastatin on carotid IMT in Japanese patients with hyperlipidemia who developed noncardioembolic ischemic stroke. Design: This is a substudy of the J-STARS, a multicenter, randomized, open-label, blinded-end point, parallel-group trial to examine whether pravastatin reduces stroke recurrence in patients with noncardioembolic stroke. The patients are randomized to receive pravastatin (10 mg daily) or not to receive any statins. Carotid ultrasonography is performed by well-trained certified examiners in each participating institute, and the recorded data are measured centrally. The primary outcome is change in the IMT of the distal wall in a consecutive 2-cm section on the central side of the common carotid artery bifurcation over 5 years of observation. Conclusion: The trial may help determine if the usual dose of pravastatin for daily clinical practice in Japan can affect carotid IMT in Japanese patients with noncardioembolic stroke.