 It ensures that school leaders have the knowledge, skills, and tools to effectively set direction for teachers, support their staff in improving instructional practices, and design a high-performing school organization that is rooted in professional learning.The program combines best practices in teaching and learning, subject-area content knowledge, and leadership knowledge and practices using an approach with proven results in preparing top-flight instructional leaders.NISL's Executive Development Program (EDP) is now the most widely used, rigorous school leadership development program in the country with more than 12,000 school leaders trained across 27 states.