School principals are responsible for the quality of their schools. The effectiveness of a school leadership including principal's qualification of personality, knowledge, experiences as well as abilities of innovation, flexibilities and coordination, in specific and general. In a changing education, the tasks of managing schools are becoming much more complex and professionalized. School principals need to be able to take a wide variety of roles: Instructional leader, transformational leader, integrative leader, co-operative leader as well as knowledge manager and the learning organization developer. For promoting school quality and accountability, a principal has to facilitate distributive leadership, collective teacher efficacy, and collaborative climate, to develop a strong focus on the educational objectives, and to focus explicitly on learning and change.