Literacy intervention research tests our best ideas about instruction and forges a pathway forward toward deeper and more nuanced understandings of how children think, communicate, and learn. This chapter describes the components of the development of literacy interventions, explaining how to construct and evaluate each component in sequence to generate robust, reliable evidence for practice. In doing so, the chapter discusses some of the specific contexts of, and challenges for, literacy intervention research in deaf education. In order to illustrate important considerations for designing and interpreting literacy intervention studies in this context, two case studies of interventions developed or applied with deaf and hard-of-hearing children are included. [This chapter was published in S. R. Easterbrooks and H. M. Dostal (Eds.), "The Oxford Handbook of Deaf Studies in Literacy." Oxford, UK: Oxford University Press.]