Response to Intervention (RTI) is a school-wide, integrative approach to instruction and intervention that provides a continuum of services to all students, both within general and special education. Further, RTI focuses on the frequent monitoring of student progress using formative and summative assessments, and providing students with differentiated and evidence-based classroom instruction. Thus, RTI can be viewed as a framework of service delivery for addressing the needs of all students which embeds best practice and effective instruction in the classroom as well as scientific, research-based intervention. In this first report of a three-part Special Report Series on RTI in Indiana, the research on the effectiveness of RTI is examined in greater depth. A discussion of the current status of federal regulations regarding RTI, a summary of Indiana's compliance efforts and adaptations of the RTI framework, and a description of the core components of RTI follow. The report concludes with brief information regarding the stages of implementation, the importance of fidelity of framework implementation, parental involvement, and a few of the common misconceptions regarding RTI. (Contains 2 figures.)