Endothelial dysfunction is thought to be an important factor in the development of atherosclerosis. Over the past decade, a non-invasive technique has evolved to evaluate flow-mediated vasodilation (FMD), an endothelium-dependent function, in the brachial artery. FMD decreases with increasing age and subjects with diabetes mellitus, hypercholesterolemia, smokers and hypertension have decreased FMD. There are a few concise studies reporting that FMD predicts cardiovascular events. However, the assumption that focal measurement of brachial artery FMD predicts coronary artery disease deserves further investigation.