Bilateral internal mammary artery grafting is associated with improved long-term patient outcomes. In situ right internal mammary artery grafting of the obtuse marginal artery, through the transverse sinus, is often limited by conduit length. We describe the technique of retrocaval positioning of the right internal mammary artery graft to extend its functional length for grafting of the circumflex territory. With careful surgical technique, this procedure can be performed safely during routine coronary bypass operations.