 Second, based in large part on international benchmarking research conducted by its parent organization, the National Center on Education and the Economy, several of the highest-performing education systems in the world use a similar strategy to leverage school principal leadership development as a foundation of their improvement approach.NISL's advanced credentialing system will give principals a transparent, codified and respected leadership development system that supports and rewards them as they progress through their careers—as it does in the world's top-performing education systems.The advanced credentialing system will empower principals, building their capacity as instructional leaders to improve teacher effectiveness and increase student achievement—across whole schools and whole districts.