"Phonological Awareness Training plus Letter Knowledge Training" is a general practice aimed at enhancing young children's phonological awareness, print awareness, and early reading abilities. Phonological awareness, the ability to detect or manipulate the sounds in words independent of meaning, is a precursor to reading. Phonological awareness training without letter knowledge training can involve various training activities that focus on teaching children to identify, detect, delete, segment, or blend segments of spoken words (i.e., words, syllables, onsets and rimes, phonemes) or that focus on teaching children to detect, identify, or produce rhyme or alliteration. The added letter knowledge training component includes teaching children the letters of the alphabet and making an explicit link between letters and sounds. Both skills are related to beginning reading. Three related What Works Clearinghouse (WWC) intervention reports review two curricula for phonological awareness -- "DaisyQuest" and "Sound Foundations" -- and a similar practice -- "Phonological Awareness Training" without letter knowledge training. One study of "Phonological Awareness Training plus Letter Knowledge Training" met the WWC evidence standards and two studies met WWC evidence standards with reservations. Together, these three studies included more than 230 preschool children from upstate New York, two Midwestern communities, and another unidentified state. They examined intervention effects on children's oral language, print knowledge, phonological processing, early reading/writing, and cognition. Most of the children studied were from economically disadvantaged backgrounds, and about one-fourth of the children were raised in non-English-speaking families. This report focuses on immediate posttest findings to determine the effectiveness of the intervention. "Phonological Awareness Training plus Letter Knowledge Training" was found to have potentially negative effects on oral language, positive effects on print knowledge, potentially positive effects on phonological processing and early reading/writing, and no discernible effects on cognition. [This publication was produced by the What Works Clearinghouse. Three studies are reviewed in this intervention report: (1) Gettinger, M. (1986). Prereading Skills and Achievement under Three Approaches to Teaching Word Recognition. "Journal of Research and Development in Education," 19(2), 1-9; (2) Pietrangelo, D. J. (1999). Outcomes of an Enhanced Literacy Curriculum on the Emergent Literacy Skills of Head Start Preschoolers. "Dissertation Abstracts International," 60(4), 1014A. (UMI No. 9927614); and (3) Roberts, T., & Neal, H. (2004). Relationships among Preschool English Language lLarners' oral proficiency in English, Instructional Experience and Literacy Development. "Contemporary Educational Psychology," 29(3), 283-311.]