Thoracic aortic calcification (TAC) is associated with adverse cardiovascular outcomes, and for the cardiovascular imager, is predominantly encountered in 4 settings: 1) incidentally, for example, during a coronary artery calcium scan; 2) as part of dedicated screening; 3) in the evaluation of an embolic event; or 4) in procedural planning. This review focuses on TAC in these contexts. Within atherosclerosis, TAC is common, variable in extent, and begins in the intima with a patchy distribution. In metabolic disorders, aortitis, and radiation-associated cardiovascular disease, calcification preferentially involves the media and is often more concentric. As an incidental finding, atherosclerotic TAC provides limited incremental discriminative value, and current data do not support screening. After an embolic event, the demonstration of thoracic atheroma provides diagnostic clarity, but has limited treatment implications. Before any procedure, the plan often changes if the most severe form of TAC, a porcelain aorta, is discovered. (J Am Coll Cardiol Img 2018; 11:1012-26) (C) 2018 by the American College of Cardiology Foundation.