Reddin於1967年提出三層面領導理論，主張在領導過程中，除領導者的作為外，更須注意的是自身的領導效能，以及應對不同情境的能力。該理論的三個層面分別為工作、關係及效能，以工作和關係層面區分成四種基本的領導形式―關注型、整合型、盡職型與疏離型。本研究旨在從三層面領導理論反思我國108課綱下學校領導者的領導效能，深入探討理論內容，以剖析領導效能的內涵，接著將其與學校領導者的領導效能連結。從各領導形式中發現，課程領導與教學領導為影響領導效能之關鍵。因此，研究者藉三層面領導理論，系統性探究學校領導者的領導效能，透過領導理論的古今對話，希望對學校領導實務帶來啟示與建議，使學校領導者有效因應108課綱為學校所帶來的轉變。

Scholar W. J. Reddin proposed The 3-D Management Style Theory in 1967. He put emphasis on leaders’ behavior and especially leadership effectiveness during the leadership process, as well as the ability to respond to different situations. The theory contains task orientation, relationship orientation, and effectiveness. It is divided into four basic forms of leadership at the task and relationship level—Related, Integrated, Dedicated and Separated. The research focuses on the leadership effectiveness of school leaders under Curriculum Guidelines of 12-Year Basic Education in Taiwan (the abbreviated form is 108 curriculum guidelines) through the theory. In the research, we explore the 3-D Management Style Theory in depth, analyze the content of leadership effectiveness, and then link it with the leadership effectiveness of school leaders. Among the various kinds of leadership, curriculum leadership and instruction leadership is the key to the effectiveness of the leadership. Therefore, with the help of The 3-D Management Style Theory, we explore the leadership effectiveness of the school leaders systematically and begin our dialogue between ancient and modern leadership theory. We hope that this research can help school leaders confront the transition and difficulties caused by 108 Curriculum Guidelines Also, by this research, school leaders in Taiwan can react effectively to the changes happens in school under 108 Curriculum Guidelines.