Transposition of the great arteries, with or without ventricular septal defect, and sinus of valsalva aneurysm (SVA) are lesions with well-established surgical therapies associated with excellent early and late outcomes. They have never, however, been reported as coexisting lesions. Their occurrence together has significant implications regarding sites of origin and rupture or obstruction in light of the altered relationships of the arterial roots and the ventricular masses. We report the diagnosis and successful treatment of a neonate with d-transposition of the great arteries with intact ventricular septum, and unruptured SVA. The implications of the altered spatial relationships in the patient with transposition and SVA are discussed. Our understanding of the morphogenesis of SVA may be impacted by this novel association as well.