The Center for Educational Leadership (CEL) is dedicated to eliminating the achievement gap that continues to divide our nation's children along the lines of race, class, language and disability. CEL believes the nexus for eliminating the gap lies in the development of leadership capacity―specifically nurturing the will to act on behalf of the most underserved students while increasing leadership knowledge and skill to dramatically improve the quality of instruction. As a nonprofit center within the University of Washington College of Education, our access to current research and best practices makes our work toward this goal especially effective. Our Theory of ActionCEL's work rests upon the critical assumption that the single most important factor in supporting student learning is the quality of classroom instruction. We know that in order to support excellent teaching, school leaders and teachers need to acquire and develop expertise about what constitutes high quality instruction. To achieve that goal, CEL develops the leadership skills, content and instructional knowledge and abilities of teachers, school administrators, and district leaders.