The CHILLAS study is planned to evaluate whether intensive treatment with statins for 2 years results in a reduction of cardiovascular events in patients with ACS. A total of 1,600 patients will be randomly assigned to receive intensive statin therapy (atorvastatin, 20 or 40 mg/d, or equivalent dose of other statins) or moderate therapy (atorvastatin, 10 mg/d, or equivalent dose of other statins). Both groups receive dietary counseling. Over a 2-year follow-up period, the primary outcome measure is the time to occurrence of cardiac death, nonfatal acute myocardial infarction, revascularization with either percutaneous coronary intervention or coronary-artery bypass grafting, documented unstable angina or severe heart failure requiring emergency hospitalization, and stroke. The planned duration is between December 2006 and December 2009.