Response to Intervention (RtI) provides a framework for guiding instruction for all students. The legal basis for RtI is in the 2004 reauthorization of the Individuals with Disabilities Education Act (IDEA) which allows schools to use a process that determines if a child responds to scientific, research-based intervention. This process involves progress monitoring and ongoing customized evidence-based interventions as a guide for instructional intervention and eligibility decisions. RtI represents a fundamental shift in how students' difficulties are conceptualized and require systemic change in how students' needs are addressed through assessment and intervention strategies.