Strong system-wide support is increasingly being identified as playing an important role in policy efforts aimed at increasing student achievement(Hightower, Knapp, March, and McLaughlin: 2002). Yet current research often views district and other system-wide support as largely governance changeswithout substantive linkage to school improvement outcomes (Cuban and Usdan: 2003). In this volume we seek to deepen our understanding of the role ofschool districts and system-wide initiatives through a series of case studies that focus on how school districts and system-wide actors facilitate policyinnovation and reform initiatives that are designed to improve student achievement. Through both quantitative and qualitative studies from diverse settingsacross the country, chapters in this volume examine the role of instructional technology, alternative accountability practices, management and partnershipreforms, and school improvement efforts through new incentive and support practices. While challenges remain, these case studies demonstrate how districtssupport and facilitate school change aimed at improving student achievement.