This FOCUS on Results document provides the reader with a basic understanding of Response to Intervention (RtI). Part one of a two-part series on RtI, this document provides RtI guidance and technical assistance to Michigan school districts. This document shares the national perspective on RtI, as provided by the National Association of State Directors of Special Education (NASDSE) in its book, Response to Intervention: Policy Considerations and Implementation, published in 2005.