Social network analysis (SNA), a methodological approach that enables the mathematical examination of interprofessional relationships, can be an important tool for understanding and leveraging the social relationships that support and restrain instructional innovation and the quality and pace of school reform initiatives. In this article, we explicate the conceptual underpinnings of SNA and summarize how it has been used in a range of preK-12 educational evaluation contexts. A school-based case study is presented in which school leaders examined formal and advice-seeking networks among teachers, staff, and administrators and used the findings to reduce teacher isolationism, promote efficient communication, and increase system capacity for instructional innovation. Challenges associated with SNA for educational evaluation and school improvement are also discussed.