In an effort to reverse the purported crisis in U.S. public schools, the federal government, states, districts have mandated policies that favor standardized approaches to teaching and assessment. As a consequence, teachers have been relying on teacher-centered instructional approaches that do not take into consideration the needs, experiences, and interests of their students; this is particularly pronounced with English learners (ELs). The widespread implementation of these policies is particularly striking in California, where more than 25% of all public school students are ELs. This volume reports on three studies that explore how teachers of ELs in three school districts negotiated these policies. Drawing on sociocultural and poststructural perspectives on agency and power, the authors examine how contexts in which teachers of ELs lived and worked influenced the messages they constructed about these policies and mediated their decisions about policy implementation. The volume provides important insights into processes affecting the learning and teaching of ELs.