This article provides an overview of research on intensive reading interventions to inform Tier 3 instruction for students with reading disabilities. Tier 3 interventions are typically provided to those students who demonstrate inadequate progress after receiving less intensive Tier 2 interventions. A conceptual overview of Tier 3 interventions within a Response to Intervention model is provided, along with a review of research on effectiveness of instructional practices for students with significant reading difficulties. (Contains 2 tables.)