Cardiac veins have long stood in the shadow of their more extensively studied counterparts, the coronary arteries. The clinical importance of the coronary venous system, nonetheless, should not be underestimated. Intricate and beneficial therapeutic options are increasingly being developed that depend on knowledge of the structure of this venous network. Such interventions have been shown greatly to promote cardiac health, and to enhance the efficacy of cardiac pacing. A comprehensive appreciation of the architecture of the coronary venous system, therefore, is crucial to optimal cardiac care. It is possible to provide an overview of the arrangement of the cardiac veins, with the larger veins draining to the coronary sinus, and thence to the right atrium, but with smaller and minimal veins draining directly to the cavities of the atrial chambers. The venous pathways, nonetheless, are highly variable, making exceptions the commonly accepted rule. As such, unique solutions for imaging, and simple attentiveness to possible venous variations, can greatly enhance clinical outcomes. For example, identifying the diameter, course, and valves of the cardiac veins allows for anticipation of impediments during interventional procedures, and allows for informed clinical decision-making. Also of significance is awareness of alternate arrangements that may be encountered in terms of venous drainage, and the importance of intramural venous collecting spaces in these patterns. The objective of our review, therefore, is to explore and describe the anatomical distribution of the coronary veins Clin. Anat. 22:129–145, 2009. © 2008 Wiley-Liss, Inc.