This action research (AR) case study examines how Sensemaking Theory (ST) is used in professional development to improve how Response to Intervention (RTI) coordinators at the elementary level understand the process of student supports. The AR team develops and implements interventions to aid RTI coordinators in gaining a stronger functional understanding of the RTI process. Elementary school level RTI Coordinators, with a common middle school feeder pattern, participate in professional development targeted at improving their understanding of Response to Intervention (RTI) and best practice implementation. By implementing pre-intervention RTI Implementation Checklists and pre/post semi-structured interviews, the researcher investigates changes shaped by implementation of professional development to address the following questions:1. How do RTI coordinators at the elementary level make sense of the implementation process?2. How might professional development be used to improve coordinators understanding of RTI?3. How might the work of an action research team improve the implementation of RTI in an elementary school?Findings suggest elementary RTI coordinators develop a stronger understanding of proper RTI implementation and support through the action research process. Data generated by this case study also indicate elementary RTI coordinators currently have adequate resources to support proper implementation of Response to Intervention best practice.