Traditionally, researchers and mathematics education practitioners have been engaged in parallel play, yet they have been segregated by the norms and cultural practises of their distinct institutions and professional reward systems. Rarely do mutually dependent and informing intellectual pathways emerge. This book explores what happens when tradition is disrupted by one purposefully designed research and practise pathway.This book offers insights into, and examples of, developing mutually interdependent research and practise processes as part of efforts to improve teacher and leadership capacity, as well as positively influence student learning and related outcomes. This book raises valuable questions for the mathematics education community.What forms have research and practise pathways taken? What lessons have been learned from collaborations?These questions are examined to illustrate where strategic partnerships have linked research to both the design and implementation of practise and programmatic endeavors and to generate evidence to guide both educational decision making and routine modifications related to school mathematics.Editor William F. Tate offers remarks about the future of research and practise collaborations in mathematics education and maintains that research and practise collaborations should be a standard regimen in movements to improve mathematics teaching and learning.