In this volume’s opening chapter, Joining Worlds: Knowledge Mobilization and Evidence-Informed Practice, chapter authors and book editors Joel Malin and Chris Brown provide relevant background and describe the purpose of the volume. It includes a definition of evidence-informed practice (EIP) and outlines challenges and benefits of making EIP a reality in schools and school systems. It also argues that brokerage is a necessary and high-leverage strategy for doing so. Several additional key terms are defined and explained, and the book’s conceptual framework is introduced – it sets out three key roles for brokers and draws attention to several key dimensions along which they vary. The book then provides a preview of the book’s remaining contents.