There is good reason why a book on deafness should be included in a series devoted primarily to second languages in applied linguistics. The fact is that the prelingually deaf and speakers of other languages share many of the same problems in learning English; insights from work with either deaf or hearing populations, therefore, are often of interest to applied linguists working with the other group.

About 10% of the deaf population in the United States has at least one deaf parent (Rawlings and Jensema, 1977), and in a large majority of these families American Sign Language (ASL) is used in the home and is the children's first language. For this group English is learned either as a second language at school, just as it is for hearing speakers of other languages, or sometimes as another first language from bilingual parents.

About one third of all deaf children in the United States are enrolled in residential schools (see American Annals of the Deaf, 1985, p. 132). This figure includes most of the children of deaf parents and many other deaf children. In this environment, where Deaf culture predominates, ASL is usually the medium of social communication among peers. Thus, the children of hearing parents not already fluent in that language learn it quickly as they are socialized into the deaf community. ASL then becomes their primary language, and English is reserved for academic purposes and for conversing with hearing teachers.