Abstract: Three theories, phonological hypothesis, perceptual hypothesis, and double-deficit, are generally proposed for the causes of English developmental dyslexia (DD). The first takes phonological deficit for the core problem of DD, and the second emphasizes that dyslexics have more fundamental visual-auditory perceptual processing deficit, especially auditory temporal processing deficit. The third, Double-deficit hypothesis, considers both the phonological and rapid naming deficit cause reading failure. Many treatment programs based on these hypotheses are contrived to improve reading performance of DD. Several typical treatment programs, which are theoretically based upon phonological deficit, auditory temporal processing deficit and double-deficit hypothesis, are introduced in the paper

Key words: developmental dyslexia, phonological treatment, Fast ForWord, RAVE-O