This third volume of the Deaf Education Series attempts to tie together decades of research on the language and literacy development and challenges of d/Deaf and hard-of-hearing children through proposing an alternative framework called the Qualitative Similarity Hypothesis. The premise of the hypothesis is that all learners, deaf and hearing, learn similarly through similar strategies, but perhaps at different stages or ages, depending on circumstances. It also incorporates personhood, the notion that all children and students should be treated on an equal basis.

The book’s nine chapters address a definition of the hypothesis: a review of research on English language development in d/Deaf, hard-of-hearing, and hearing learners; a description of English language learners; a summary of approaches to English literacy development; a review of instructional strategies; discussion of various epistemologies and methodologies for conducting research in language and literacy development; and a special chapter with two essays analyzing and critiquing the authors’ presentation of the Qualitative Similarity Hypothesis. The special chapter offers interesting counterpoints that provide the authors the opportunity to further clarify their intentions and goals with this hypothesis.

The depth and breadth of literature reviewed in each chapter of this text will provide the reader with substantial background and context for considering the ongoing challenge of promoting the language and literacy learning of d/Deaf and hard-of-hearing students. In their final chapter, the authors remind readers and scholars that the Qualitative Similarity Hypothesis in the context of this population focuses on the acquisition of “through-the-air English (i.e., speaking and/or signing) and English literacy (i.e., reading and writing).” The authors stress that the acquisition of English by any individual as a first or second language will be developmentally similar, whether they are d/Deaf, hard-of-hearing, or hearing, to others in similar first or second language learning circumstances. A key difference that perhaps explains the perpetual lag of d/Deaf learners behind their hearing peers is that many are attempting to learn a written language (English) without sufficient exposure to its written or spoken form. Another key difference is that many d/Deaf learners never quite attain proficiency in a primary language such as American Sign Language because they do not use it at home, only at school. The acquisition process is influenced by multiple factors and variables, such as demographics, all of which provide contexts and opportunities for empirical research conducted within the Qualitative Similarity Hypothesis.

The authors assert that effective educational research is essential to teacher preparation, and they advocate for sustained and systematic efforts in initiating and evaluating intervention strategies. This text will be useful for students and researchers interested in the English language and literacy development of d/Deaf and hard-of-hearing learners. It may be especially helpful to doctoral students seeking dissertation research topics in this area.