Teacher leadership is often an underutilized and unrealized resource in elementary schools. Teacher leadership manifests itself in a variety of ways, via formal and informal roles. This study aimed to understand the development, expression, and influence of teacher leadership in Wisconsin public elementary schools via the perspectives of teacher leaders and their principals. Based on a conceptual framework developed from four strands of work (distributed leadership, teacher learning, teacher leadership, and relational trust), this study investigated the organizational and social structures and conditions that advance teacher leadership via interviews and focus groups with teachers and principals, institutional mapping, and an analysis of school documents. The Listening Guide, a psychological inquiry method, was used to attend to the voices of teacher leaders. Findings indicated that teacher leadership develops from within, based on professional learning and experience, and is advanced through healthy school cultures in which leadership is shared and teachers participate in decision making. Furthermore, principals fuel teacher leadership by establishing and sustaining organizational structures and systems that foster collaboration, a sense of belonging, teacher learning, and shared purpose. Ultimately, this study surfaced the voices of teacher leaders to improve our understanding of their influence, the ways in which they transcend boundaries, and their sense of self as professionals, to help inform the advancement of teacher leadership in schools.