Fetal tracheal occlusion accelerates lung growth and corrects the often fatal pulmonary hypoplasia seen in fetuses with congenital diaphragmatic hernia. Fetoscopy presents a unique opportunity to glimpse into the world of the fetus, but its use, until recently, has been limited to diagnostic and simple procedures. Using fetoscopic techniques ("Fetendo"), we now report successful tracheal occlusion in a 30-week-old fetus for the treatment of congenital diaphragmatic hernia.