This article reviews the use of intraoperative echocardiography during repair of congenital heart defects. Although initial experience was generated using epicardial transducers, there has been a trend in recent years toward the use of transesophageal echocardiography (TEE) in the operating room. This has encouraged increased involvement from cardiologists and anesthesiologists. New probe designs have provided biplane imaging via the TEE approach in infants weighing more than 2.5 kg. Smaller infants may still require epicardial imaging, so it is helpful for surgeons to maintain some skill in this technique. This article reviews the utility of intraoperative echocardiography for various congenital heart defects by providing examples from our experience at Duke University Medical Center since 1987 with close to 2,000 cases. Furthermore, we review and report for the first time our experience with TEE since 1993 in the operating room during infant heart surgery (493 patients). Along with this experience, we provide a review of important series in the literature to outline recommendations for the use of echocardiography during infant heart repair.