Research about how teachers construct practitioner researcher identities is central to teacher education and professional development because it provides insight into how teachers continue to learn about and implement practices that meet the needs of their students. The paper explores how one fourth-grade teacher (Holly) constructed her practitioner researcher identities over two years. It draws upon data gathered from a year-long Teacher as Researcher course and a monthly practitioner researcher group (Triad Teacher Researchers) associated with a Southeastern university in the United States. In particular, this paper examines moments of tension when Holly was challenged to negotiate multiple identities in order to situate herself as a practitioner researcher within multiple contexts. Findings suggest that learning to 'become' a practitioner researcher is an identity process that involves moments of tension that are best supported through a collaborative community. The paper concludes with implications about how to facilitate spaces of identity work through various types of reflective practices in courses and groups. (Contains 1 table.)