The invention features methods and compositions for assessing risk, particularly immediate risk, of thrombotic events in patients with suspected or known vascular disease, and more particularly to assessing risk of thrombotic events in patients with coronary artery disease, particularly acute myocardial infarction, stroke, unstable angina, stable angina, or restenosis. Risk of thrombosis can be assessed by analysis of platelet reactivity and/or velocity of thrombin or fibrin formation, and determining whether the patient has a score associated above a risk threshold value. In other embodiments, risk of thrombosis in a patient is evaluated in the context of a profile generated from values obtained from one or more assays that evaluate various factors associated with thrombosis and/or atherosclerosis.