Teaching young children to read is the most critical educational priority facing this country. Encouragingly, this is an area where some of the best and most rigorous scientifically based research is available. The Reading First program helps States and districts apply this research--and the proven instructional and assessment tools consistent with the research--to teach all children to read by focusing on what works, and supporting proven methods of early reading instruction in classrooms. The program provides assistance to States and districts in selecting or developing effective instructional materials, programs, learning systems and strategies to implement methods that have been proven to teach reading. Reading First also provides assistance for the selection and administration of screening, diagnostic and classroom-based instructional reading assessments with proven validity and reliability, in order to measure where students are and monitor their progress. Taken together, the complementary research-based programs, practices and tools required by Reading First will give teachers across the nation the skills and support they need to teach all children to read fluently by the end of third grade. This overview identifies components of effective reading programs (phonemic awareness; phonics; vocabulary development; reading fluency, including oral reading skills; reading comprehension strategies), defines scientifically-based research and the critical evidence for evaluation of this research, and state responsibility to ensure that only programs based on such research are funded by Reading First. Practices and strategies for classroom instruction, professional development, program assessment and the application process are discussed. A list of definitions, evaluation checklist, research findings/program component cross-reference, and suggested resources are included. [This document was produced by the Commonwealth of Virginia, Virginia Department of Education, Office of Elementary Instructional Services.]