This introduction presents an overview of key concepts discussed in the subsequent chapters of this book. The book is about spina bifida and hydrocephalus many of the physical, intellectual and family problems described in it are shared by children handicapped in other ways and the suggestions made here about how these problems can be met will also be relevant to them. Parents of spina bifida children frequently have anxieties about their children's health, especially in the early years: severe damage to the kidneys caused by urinary infections and blockage of the shunt which controls the hydrocephalus may have extremely serious consequences. Children with congenital hydrocephalus which is not associated with spina bifida or with hydrocephalus acquired in early childhood, perhaps from meningitis, are likely to have very similar learning difficulties. The children were tested individually on a battery selected to elicit information about overall intellectual ability and sub-test performance patterning; verbal ability; visuo-motor and visuo-perceptual ability; and hand function.