This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book discusses some of the models which have guided people's thinking, such as the deficit research model, together with a more functional model derived from linguistics. It focuses on existing commentary; for example, in relation to the reading and writing skills of deaf children. The book examines the reading and writing development of children with mild and severe hearing losses in relation to the language framework. There is a complex set of arguments on either side for the role of speech or sign language in the teaching of the severely hearing-impaired. The book considers the different approaches which could be made towards remediating the literacy problems of hearing-impaired children. It is important for teachers to be aware of the likely impact of their intervention and which aspects of the child's abilities and skills are involved.