Through a basic qualitative approach this study examined the perceptions of high school counselors use of district-embedded Early Warning Systems (EWS) to increase efficiency and understanding of their caseload. In the past, studies have only examined implementation of EWS and the various indicators within an EWS, but most have not explored counselor or user perception. This study focused on school counselors' direct usage of an EWS and other data systems to inform practice and develop understanding and efficiency over their caseload. The job of a school counselor is demanding, and the national average of counselor to student ratio is well above the recommended ratio outlined by the American School Counselor Association. Results from this study indicate an increased understanding and efficiency regarding caseload when data practices are regular, intentional, and explicit. The results lead to specific recommendations related commonly created data indicators based on research, regularly scheduled data routines, and increased professional development. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]