Teacher leadership is the process by which teachers, individually or collectively, influence their colleagues, principals, and other members of the school communities to improve teaching and learning practices with the aim of increased student learning and achievement. Such team leadership work involves three intentional development foci: individual development, collaboration or team development, and organizational development. (pp. 287-288)

The push for teacher professionalism and increased leadership responsibilities stems from the recognition that teachers, as they interact with students on a daily basis, possess the expertise to make crucial decisions concerning instruction and the enhancement of schools. As noted by Howey (1988) and Livingston (1992), teachers are better equipped to implement changes in a comprehensive and consistent manner. Furthermore, the drive to expand teacher responsibilities is driven by the continuous imperative to draw and retain skilled educators.

A teacher leader is someone who impacts students and teachers outside his or her classroom. Teacher leaders are the heart of a school. They are the silent partners in decision-making. They are always available to set an example and exemplify the mission and vision of the school. Through daily commitment to students and teachers, they support and sustain the life and culture of a school.

 "Leadership in instructional practice means something more than being the best possible teacher within the four walls of one classroom— it means reaching out and sharing great teaching with others, including fellow educators, but also extending to a broad range of stakeholders. Successful teacher leaders do not keep their effective practices to themselves; they spread that knowledge to others in order to benefit all students." http://www.nbpts.org/

From: Leading in Sync: Teacher Leaders and Principals Working Together for Student Learning Publisher: Association for Supervision and Curriculum Development