A trend toward use of less invasive, nonsurgical approaches to the treatment of congenital heart disease has developed. Although transcatheter valve replacements and ventricular septal defect closures have already been performed in children, many other techniques and devices are being developed for the palliation of children with a single ventricle. Several groups have already established catheter-based procedures for the creation of Fontan communications, and others have performed nonsurgical pulmonary artery banding. Additionally, fetal catheter-based interventions are being developed for the treatment of severe congenital heart disease in utero. Because this trend toward catheter-mediated treatment is certain to continue, care must be taken to regulate safely the introduction of novel techniques and devices into clinical use in pediatric cardiology.