That there is a divide between research and practice is a common lament across policy-oriented disciplines, and education is no exception. Rhetoric abounds about the role research plays (or does not play) in the improvement of schools and classrooms, and policy makers push solutions that are rooted in assumptions about the way that research "should" influence practice. Yet few people have studied the relationship between research and practice empirically. This book presents findings from a series of interlocking case studies of nationally visible R&D projects, with a unique focus on how researchers and practitioners actually worked together, and the policy, social, and institutional processes that either enabled or hindered their work. The book investigates the dynamics of cross-institutional collaboration and the relationship between tool design, teacher learning, and the implementation of research-based approaches. It also explores conditions for learning in schools and the role of evidence in district decision making. By investigating the roles played by research and practice in these ten educational improvement efforts, the book illuminates lessons for those who seek to do this kind of work in the future. It concludes by suggesting implications for designers, funders, school and district leaders, and universities. Contents include: (1) Reframing the Problem of Research and Practice (Mary K. Stein and Cynthia E. Coburn)--Part I: Fostering Partnerships for Educational Innovation; (2) The Middle School Mathematics through Applications Project: Supporting Productive Collaborations During Two Different Phases of Curriculum Design (Randi A. Engle); (3) The Center for Learning Technologies in Urban Schools: Evolving Relationships in Design-based Research (Laura D'Amico); (4) Examining a Novel Partnership for Educational Innovation: Promises and Complexities of Cross-institutional Collaboration (Lisa Rosen)--Part II: Role of Tools in the Relationship Between Research and Practice; (5) Success for All: Using Tools to Transport Research-based Practices to the Classroom (Amanda Datnow and Vicki Park); (6) Tools to Deepen Practitioner's Engagement with Research: The Case of the Institute for Learning (Gina Schuyler Ikemoto and Meredith I. Honig); (7) QUASAR: The Evolution of Tools to Support Educational Improvement (Juliet A. Baxter)--Part III: Developing Conditions to Foster Knowledge Development in Schools; (8) Building Demand for Research through Lesson Study (Rebecca Perry and Catherine Lewis); (9) The National Writing Project: Anatomy of an Improvement Infrastructure (Laura Stokes)--Part IV: Research and Decision Making in School Districts; (10) The Partnership for District Change: Challenges of Evidence Use in a Major Urban District (Cynthia E. Coburn); (11) Research-to-Practice: A Case Study of Boston Public Schools, Boston Plan for Excellence and Education Matters (Lea Hubbard); and (12) Key Lessons About the Relationship between Research and Practice (Cynthia E. Coburn and Mary Kay Stein). Foreword (Deborah Stipek), References and a list of contributors are included. Research Methodology is appended.