This investigation was undertaken to identify the graphonemes inherent within the structure of those English words most likely making up the reading vocabulary of elementary school children. Such knowledge was deemed to be important in determining which words should be included in the content of reading materials designed for initial reading instruction. The hypotheses were that the graphoneme is a readily identifiable matrix within the structure of English words and that a frequency distribution of graphonemes occurring in the vocabulary of elementary school children would provide priorities for teaching purposes. This study dealt only with the decoding process. In identifying words, the 1962 edition of the Thorndike Barnhart Beginning Dictionary was examined and every tenth word marked. Seven generalizations were concluded from the data. The study also lent validity to the assumption that the graphoneme is a useful matrix to be recognized within a word and enforced the concept of movement away from monosyllabic toward the early introduction of multisyllabic vocabulary. References are included. (NH)