This book describes the three-tiered model of reading intervention, which identifies and provides services to students with reading disabilities. It shares what is known about research-validated practices for each tier of reading interventions. The first tier, primary intervention, provides a fundamentally sound core reading program for all students in early grades. Secondary intervention includes supplementary reading instruction for children who experience early difficulties learning to read. The third tier, tertiary intervention, includes additional instruction for children who still have problems with reading despite the supplemental instruction. Children in the third tier would likely have learning disabilities and would qualify for special education services. The volume will summarize research findings about effective reading intervention at each of the three tiers, for whom specific interventions have been validated, and under what conditions or in what settings interventions have been effective.