This article defines open myelomeningocele and describes its development in the embryo. The anatomic features of the neural placode, pia-arachnoid, and dorsal versus ventral roots are well described. The surgical technique and prenatal and postnatal care are detailed. Anomalies associated with open myelomeningocele are also described. The concept of a team approach to treating children with myelomeningocele and their families is addressed.