Quality high-school advising is essential to ensuring access to higher education. However, while efforts are being made in a number of areas to improve access to higher education, there has not yet been enough work done to assess the impact of DEI initiatives on post-secondary advising and, in turn, on college access for underserved students. Thus, in an attempt to start filling the knowledge gap concerning the impact of DEI-focused post-secondary advising on college access, this study sought to explore how and if single New Jersey school district's efforts in DEI have had an impact on its post-secondary advising processes. Specifically, this study sought to better understand the impact of DEI work on schools' post-secondary advising process, including how such work can change systems/processes in schools to improve student access to post-secondary education. This study utilized a mixed methods approach to collect and analyze the data, with two research questions utilizing a qualitative approach and one utilizing a quantitative approach to best understand the data. Research Question 1 focused specifically on the advising process and the guidance department; in other words, it focused on the direct experience that a student would have in the Strawberry Mountain School District. Research Question 2 examined the district as whole, including all of the various components that would enable students to access and pursue post-secondary education. Research Question 3 sought to achieve a metric for district success by comparing SMSD results to State of New Jersey results utilizing the accountability measures found in the annual New Jersey School Performance Reports. After analysis of the combined quantitative and qualitative data, the study was able to conclude that changes were, in fact, made and that the SMSD vision was successful in changing the culture of post-secondary educational access for this specific district. [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.]