The Every Student Succeeds Act (ESSA), passed in 2015, signaled a major shift in the roles of states and districts in supporting school improvement. Under ESSA, state education agencies (SEAs) and local education agencies (LEAs) have more responsibility and flexibility in developing and implementing plans, informed by local context, to support the bottom 5 percent of schools, high schools with graduation rates of less than 67 percent, and schools with chronically struggling subgroups of students. The purpose of this brief from the Center on School Turnaround (CST) at WestEd is to provide examples of how states and districts are working together to improve low-performing schools under ESSA. This brief includes a description of state and district roles in school improvement based on an analysis of 23 state ESSA plans. It also provides examples, based on interviews, of how 10 states are carrying out those roles.