Response to Intervention (RTI) employs a multi-tiered approach to providing targeted interventions for students who are at risk for school failure. With the reauthorization of the Individual with Disabilities Act (IDEA) 2004 and No Child Left Behind (NCLB) 2001 districts are given the option to implement RTI prior to student referral for special education (Prasse, 2006). The implementation of RTI requires schools to shift current educational paradigms of how services are delivered to students. The purpose of this study was to investigate the following research questions: What are the special education rates over time for the FY 08, 09, and 10 for the elementary schools N = 3 that have implemented RTI? What are elementary teachers' perceptions of RTI with respect to the following dimensions: Administrative Support, Resources, Level of Implementation, and Student Performance? How are elementary teacher perceptions of their involvement in the RTI process associated with their classroom instructional practices? A two-phase mixed method design was used to gather perceptions from a census population of teachers N = 122 from N = 3 elementary schools. The study employed the framework of Stufflebeam's (2007) CIPP evaluation model. The quantitative research used descriptive statistics to report the elementary school N = 3 special education rates from 2008 through 2010. A survey questionnaire was employed to elicit teacher perceptions relative to the implementation of RTI. The qualitative research involved focus groups to gain a deeper understanding of the survey responses and changes in instructional practices. Data analysis involved the use of descriptive statistics and ANOVA for the quantitative analysis. The coding of qualitative data generated themes that resulted in a thick narrative. Historically, the separation between general and special education has been well documented (Weishaar, Weishaar, & Budt, 2002). RTI offers the opportunity for a seamless continuum of services focusing on improving outcomes for all students (VanDerHeyden, Witt, & Barnett, 2005). Findings of the study suggest when administrative support and resources are provided to teachers when implementing RTI there is a direct correlation to a decrease (2.5%) in special education rates, a change in instructional practices, and an increase in student performance. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]