A diagnostic screening procedure for developmental dyslexia which analyzes how a child reads and writes rather than at what level, is outlined. Briefly, the test entails a presentation of a word list at each reading level to determine the child's sight vocabulary and his ability to employ word-attack skills. Following the administration of the word recognition test, the child is screened for atypical spelling patterns and given a paragraph to read from a textbook to ascertain his ability to read in context and his reading comprehension. On the basis of the distinctive reading-spelling patterns the test reveals, three correlated groups of dyslexic children have been delineated. Children in each group typically have a deficit in the ability to auditorize, a deficit in the ability to visualize or a deficit in both ability to auditorize and ability to visualize. Implications for remediation for each group are provided and diagnostic criteria are reviewed. (WW)