Cued speech is based on the hypothesis that if all the sounds in the spoken language looked clearly different from each other on the lips of the speaker, people with a hearing loss would learn a language in much the same way as a hearing person, but through vision rather than audition. Literacy is the ability to read and write proficiently, which allows one to understand and communicate ideas so as to participate in a literate society. Cued speech was designed to help eliminate the difficulties of English language acquisition and literacy development in children who are deaf or hard-of-hearing. Results of research show that accurate and consistent cueing with a child can help in the development of language, communication and literacy but its importance and use is debated. Studies address the issues behind literacy development, traditional deaf education, and how using cued speech affects the lives of deaf and
HOH children. Cued speech does indeed achieve its goal of distinguishing phonemes received by the learner, but there is some question of whether it is as helpful to expression as it is to reception. An article by Jacqueline Leybaert and Jesús Alegría discusses how children who are introduced to cued speech before the age of one are up-to-speed with their hearing peers on receptive vocabulary, though expressive vocabulary lags behind. The writers suggest additional and separate training to teach oral expression if such is desired, but more importantly this reflects the nature of cued speech; to adapt children who are deaf and hard-of-hearing to a hearing world, as such discontinuities of expression and reception are not as commonly found for children with a hearing loss who are learning sign language. Ostrander concludes that further research into these areas is needed and well justified. The editor of the
Cued Speech Journal (currently sought but not discovered) reports that "Research indicating that Cued Speech does greatly improve the reception of spoken language by profoundly deaf children was reported in 1979 by Gaye Nicholls, and in 1982 by Nicholls and Ling." In the book ''Choices in Deafness: A Parents' Guide to Communication Options'',
Sue Schwartz writes on how cued speech helps a deaf child recognize pronunciation. The child can learn how to pronounce words such as "hors d'oeuvre" or "tamale" or "Hermione" that have pronunciations different from how they are spelled. A child can learn about accents and dialects. In New York, coffee may be pronounced "caw fee"; in the South, the word friend ("fray-end") can be a two-syllable word. ==Debate over cued speech vs. sign language==