Many believe teacher leaders can play a central role in meeting the needs of students in schools, but it is presumptuous to think that teachers intuitively know how to lead their colleagues or schools without any focused support. This paper describes how one middle school mathematics teacher learned to enact leadership through an informal role as a teacher leader. The results of this autoethnographic study also reveal how the teacher’s view of leadership changed during the year of the study. As that leadership identity transitioned, the researcher found that adopting a lead-by-example and lead-learner stance supported her work with colleagues. A presentation of findings related factors that supported and hindered the transition from mathematics teacher to that of teacher leader are shared. Factors that supported teacher leadership included maintaining a disposition of continuous learning, developing a community of practice with colleagues, and developing a systems view of leading. The experiences and factors that hindered the process of becoming a teacher leader included confusion about one’s leadership role, navigating the middle ground between colleague and leader, and the lack of communication with administration. The findings in this paper suggest several courses of action for supporting emergent teacher leaders.