This yearlong qualitative multisite case study investigated ways middle and high school transition supports foster a developmentally responsive transition for students. A total of 23 participants engaged in this study, including 4 students, 4 middle school teachers, 13 high school teachers, 1 middle school principal, and 1 high school principal. Data were collected during the spring, summer, and fall of 2009, including focus group interviews, individual interviews, observations, and the collection of transition-related documents. Findings reveal transition supports, including a transition program with various activities and a ninth-grade transition course that addresses the procedural, social, and academic aspects of the move may foster a developmentally responsive transition to high school for students. However, student and educator perceptions regarding the responsive nature of these supports differed. An implication for middle and high school educators is to consider ways to strategically implement transition supports that address the procedural, social, and academic aspects of the move in a responsive way by attending to students' basic and developmental needs and transition-related concerns. Students themselves must perceive these supports as meeting their needs and addressing their concerns in order to help students during this period of schooling.