This report defines and describes an advanced model of school-based management in Prince William County, a suburban district considered to be part of the Washington, D.C., metropolitan area. It documents the shift from a "top-down" to a "bottom-up" school-based management approach based on input from parents, teachers, students, and principals within a framework of school board policy and administrative regulation; reviews five pilot school-based management plans and the concomitant functions of administrators, especially principals; summarizes the strengths and limitations inherent in implementation and realization; and predicts the changing roles of the school board and central staff as they relate to school-based management. (JAM)