This book helps mathematics leaders build a high-quality instructional programme based upon the five principles identified by the National Council of Teachers of Mathematics (NCTM, 2000): equity, curriculum, teaching, learning, and assessment, and the four leadership principles from the National Council of Supervisors of Mathematics in the PRIME Leadership Framework (NCSM, 2008): equity leadership, teaching and learning leadership, curriculum leadership, and assessment leadership. The authors provide an approach to improvement that includes: articulating the curriculum; implementing the curriculum; using effective instructional strategies; providing timely feedback; and, providing opportunities for collaboration and professional development. Leaders will find guidance on how to plan for long-term change and how to focus their time and energy towards short-term objectives, with the overarching goals of continually engaging and empowering mathematics teachers.