This chapter addresses some of the significant gaps in knowledge about teacher leadership. First, the authors describe important attributes of teacher leaders and their motivations for exercising influence. The spheres of teacher leader influence and responsibilities are described, progressing from the need for individual self-reflection to the classroom and throughout the school. The widest level of influence is on parents and the larger community. Further, the lens of teacher identity is used to examine the process by which teachers become leaders, along with the influence of beliefs, values, and a sense of agency. Next, the chapter will consider some of the influential voices and influencesInfluences on teacher leadershipTeacher leadership dialogueDialogue. It describes how the term teacher leadershipTeacher leadership obscures nuances relevant to different international contextsContexts. The argument is presented that there is an unintended but clearly discernible hegemonic dimension to our understanding of teacher leadershipTeacher leadership. This will describe the terms in relation to implicit assumptions which may be competing and are perhaps primarily based in WesternWestern thought. The chapter emphasizes the need for more context-centered interrogation of the discourse about teacher leadershipTeacher leadership, especially in relation to its cultural compatibility and sensitivity. Cultural, historical, economic, and political differences require understanding teacher leadershipTeacher leadership in global and local contextsContexts. The chapter closes by briefly describing each of the chapters in the book and how they will address gaps in current understandings of teacher leadershipTeacher leadership.