Ways in which teachers and principals respond to changing leadership roles and some practical steps that principals can take to support leadership are discussed in this article review. It focuses on five papers that explore educators' roles, offering advice on how to respond to changing expectations. "When is New: A Plan of Action" (A. W. Hart) examines ways that teacher leadership changes the principal's traditional duties. "Awakening the Sleeping Giant: Leadership Development for Teachers" (M. Katzenmeyer and G. Moller) suggests that teacher leadership can play a significant transformative part in K-12 schools, and that such teacher leaders are classroom-centered leaders who concentrate on teaching and learning rather than on organizational "nuts and bolts.""Effects of Teacher Leadership on Their Teaching Practice" (M. N. Ovando) surveyed 25 teachers who revealed that leadership roles demanded time that used to be devoted to planning periods and other free moments. "Supports and Barriers to Teacher Leadership: Reports of Teacher Leaders" (L. F. Zinn) presents research showing that the new leadership role can be difficult for teachers to master and that support is crucial to the process, such as a strong network of colleagues and administrator support. "Teacher Leaders and Their Principals: Exploring the Development of New Working Relationships" (M. A. Smylie and J. Conyers) states that once teachers assume a leadership role, they must redefine their relationship with the principal in order to reduce any role ambiguity. (RJM)