In an effort to best support student learning, school districts are seeking the most effective means of improving instruction while effectively addressing student inequities. As the focus on accountability intensifies, the use of data is paramount. Access to data alone, does not ensure quality, data-driven instruction. The lack of teacher confidence in utilizing data to drive instruction often impacts efforts to improve student performance. Districts must determine the best form of professional development to support teacher learning around data-decision making and improve data culture. This program evaluation sought evidence to determine the effectiveness of the Instructional Data Support (IDS) Program on district data culture, the extent to which the program was being implemented with fidelity, and the barriers to implementation if they existed. The IDS program consisted of two components: the implementation of i-Ready as a curricular supplement and data tool and teacher participation in coaching cycles with a site-based Instructional Data Support teacher. This evaluation employed quantitative and qualitative approaches. Data usage reports from i-Ready were analyzed over two years of implementation. Surveys were sent to all certificated staff, IDS teachers, and principals. Surveys were analyzed for insight on implementation, evidence of improved data culture, and barriers to implementation. Evaluation findings indicate the program was not implemented with fidelity across the district although implementation was higher at certain grade levels. Despite the findings around implementation, teacher and principal data demonstrates findings that the IDS program is leading to some impact on the data culture of the district, especially in the area of PLC conversations, small group instruction, and intervention. Barriers to implementation did exist, including time, communication of expectations, and lack of teacher buy-in, in one or both parts of the program. Future evaluation of the IDS program is recommended to determine the long-term and sustainable impact it has on the district data culture, and if addressing the barriers leads to increased district-wide implementation. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]