Abdominal wall defects can be divided into two groups depending on their embryological origins: gastroschisis, ectopia cordis and bladder exstrophy in one group and exomphalos in the other [1]. In practice, there is an overlap particularly with regard to bladder exstrophy, pentalogy of Cantrell and exomphalos. This chapter will focus on gastroschisis and exomphalos with bladder exstrophy being discussed elsewhere in the book.