The Every Student Succeeds Act (ESSA) gives states new flexibility to deliver on the promise of public education in the way that works best for the communities they serve--especially when it comes to building school accountability systems. These systems are among the most powerful tools at a state chief's disposal to advance ESSA's goals of "school quality and student success." They should embody a state's vision of a great education and definition of a great school, and help monitor whether it's becoming a reality for students. In this working paper, we offer some guiding principles to help state chiefs build an accountability system that reflects voices from across their communities, advances educational equity, and makes a difference for as many students as possible.