Surgery for congenital heart disease has advanced significantly in the past 50 years, such that repair of "simple" lesions, such as atrial septal defect, ventricular septal defect, and coarctation of the aorta carries minimal risk, with mortality risk much less than 1%. It was once thought successful repair of these lesions was definitively corrective. There is mounting evidence, however, that there are long-term complications after these repairs, prompting the need for continued follow-up. This review describes the current understanding of diagnosis, treatment, and long-term outcomes for these patients, with the goal of advocating for lifelong surveillance. As the perioperative care of these repairs has evolved significantly over time, so must the way in which we study these patients in the long-term.