Denver Public Schools, one of 14 districts that receive funding from The Wallace Foundation to improve principal effectiveness, is also one of a number of districts around the country emphasizing the development of principals' managers in the central office. The principal's job has changed over the last decade, going from a role that revolved around "buses, boilers, and books" to one that centers on promoting high-quality teaching and learning in classrooms. In most districts, the principal supervisor's job has not yet adapted to that change. A Wallace-commissioned study by the Council for the Great City Schools found that principal supervisors are often stretched for time, insufficiently staffed, poorly matched to the needs of their schools, and assigned to too many schools (Corcoran et al., 2013). A Council survey of administrators in 41 large districts found that principal supervisors manage fully 24 principals on average and that their duties typically extend beyond helping principals. Close to 95% of respondents said their responsibilities included "district administrative issues" while almost 73% put "district compliance issues" among their job tasks (Casserly, Lewis, Simon, Uzzell, & Palacios, 2013). The unwieldiness of the job as it is often structured can hamper a district's ability to support its principals. "Principal supervisors are the ones that are out in schools, in the field, working with principals," said Tricia McManus, director of leadership development at Hillsborough County Public Schools, the district encompassing Tampa, Fla., and another recipient of Wallace funding. "If we're going to maintain the quality of principals we're putting into that new principal role and continue their support and development, we're going to have to focus on the role that's in the schools the most." To make sure principals get the instructional support they need, school districts are experimenting with several strategies which include:(1) New training to meet new needs; (2) matching the supervisor to the school; and (3) managing the workload.