This action research seeks to understand whether an intentional investment in the leadership development of teacher leaders through input, modeling, coaching and consultation in instructional leadership team meetings will result in improved effectiveness of facilitation of professional learning communities (PLCs) by teacher leaders and whether that improved facilitation will in turn result in shared best practices among teacher participants and improved academic outcomes for students. The research was conducted in an urban elementary school with six teacher leaders. During the intervention period, teacher leaders participated in nine weeks of professional development in ILT focused specifically on facilitating the professional learning of their teams. Data was collected from research participants via self assessments of leadership competencies, facilitation skills, and overall PLC effectiveness. Additionally, video observations of PLC meetings were conducted to assess teacher leader growth in facilitation of adult learning. Teacher evaluation scores and PLC participant survey data were also analyzed to understand the effectiveness of the research interventions. Results of this action research highlight the nuanced nature of teacher leadership and its impact on professional learning. While teacher leaders reported a decrease in efficacy following the intervention period, they also reported a significant growth in their leadership competencies and in the overall effectiveness of their PLCs. Interestingly, although teacher evaluation scores improved across most teams, PLC participants reported a relatively low impact of PLCs on their instructional practice. As a whole, it appears focused leadership development for teacher leaders yielded positive impacts for the teacher leaders themselves, their teams, and their students, however, further research is needed to determine which professional learning strategies are most beneficial for strengthening teacher leadership and moving a school towards a distributive leadership model.