This article describes a data-based continuous-improvement framework that can help school teams use what the authors call "systems-level data" to support teachers in achieving successful beginning reading outcomes for all students. The authors also furnish an example of an elementary school in the Pacific Northwest that uses such a framework to evaluate students' reading progress and the system of literacy instruction. This type of continuous-improvement framework helps school teams determine whether instruction and interventions are effective across the school system and can identify instructional factors that may need modification to improve instruction in their schools. The authors contend that educators can best consider this continuous-improvement framework within an RTI (response to intervention) model of service delivery. To achieve this model, educators explicitly link student assessment data with instructional decision making by: (1) planning a multitiered model of differentiated instruction; (2) evaluating the multitiered model; and (3) creating a data-based improvement plan. These steps are recursive because schools should continuously adjust the improvement plan in response to student data. (Contains 1 figure and 3 online resources.)