Every fall, 8th graders in the School District of Philadelphia (SDP) have the opportunity to apply to five district-managed high schools other than their own neighborhood school. One of the goals of Philadelphia's tiered system of neighborhood, citywide, and special admission high schools--many with specific curricular programs--is that students find the right "fit" to complement their academic record, skills, and interests. This selective system requires students to understand the characteristics of different high schools and to assess whether they meet the admission criteria in order to make strategic application decisions. This brief examines the role of the middle school counselor in helping students navigate this process. Students may also apply to charter or private high schools in separate processes, and some counselors discussed these options with students and their parents, but this brief focuses on the SDP high school application process. This brief focuses on middle school counselors, recognizing the critical role they play in supporting students in the high school application process. It outlines best practices for counselors in the SDP, focusing on three lessons: (1) the high school application process starts in 7th grade; (2) students and parents need guidance in making high school application decisions in 8th grade; and (3) enabling conditions in some schools allow counselors to provide individualized supports to students and families in this process. It also acknowledges common challenges that counselors face in implementing these best practices. The lessons from this study apply not only to counselors but to principals, 7th and 8th grade teachers, and other school staff who seek to individually or collaboratively support students throughout this process. Appended are: (1) Counselors are Critical: Lessons and Best Practices At-a-Glance; and (2) Overview of Counselor Duties at Study Schools. (Contains 5 footnotes.)