Atherosclerosis is a systemic disease that affects most major arteries of the body and is the most common cause of premature death in the western world. It develops slowly and often asymptomatically, so that for many patients its first manifestation is sudden cardiac death, stroke, or myocardial infarction. The current gold standard for imaging atherosclerosis is x-ray angiography. However, recent advances in understanding of the pathobiology of atherosclerosis have highlighted the inadequacies of this technique and the need for better imaging approaches. The purpose of this article is to briefly outline the biology of atherosclerosis and to review the techniques available to image it, concentrating specifically on those that detect metabolic or inflammatory changes within the atherosclerotic plaque.