The revisions to federal policy reflected in ESSA suggest that federal policy makers are acknowledging the growing research-base on principal effectiveness, and responding by shaping policy to create new opportunities for innovation and improvement in principal preparation and development. Principals, as multipliers of effective practice, are a critical and fiscally prudent lever for improving and sustaining effective teaching and learning at scale. Illinois leads the nation in its attention to a comprehensive overhaul of principal preparation programs to more effectively lead PK-12 instruction. The promise of ESSA depends upon the ability of state and local educational agencies, and their partners, to harness their collective expertise and resources toward this common goal. In this case, if policy becomes tightly coupled with implementation, then Illinois could be on the verge of another major paradigm shift ultimately leading to positive school and student outcomes statewide.