Professional Learning Communities (PLCs) have shown promise as a means to meet the challenge of the No Child Left Behind Act of 2001. A problem that has surfaced is the inabilty of schools to sustain PLCs. This project study examined leadership characteristics of elementary school principals in selected school districts to determine how these characteristics shape organizational culture and provide support for sustaining professional learning communities. At the center of this initiative have been the school principals and their leadership skills. The theoretical underpinnings of this study were based on the work of DuFour and DuFour, which places leadership of the principal at the forefront of successful school improvement. A mixed-methods approach with a sequential-transformative strategy was used. Quantitative data were collected by administering the Leadership Capacity School Survey to 30 elementary principals. Descriptive statistics were used to determine which of Lambert's six critical constructs were most and least commonly practiced among the schools in the study. Qualitative data gathered through a focus-group discussion were analyzed through the typological process. Quantitative and qualitative findings indicated that broad-based, skillful participation in the work of leadership (Construct 1) was the most important leadership construct to the success of sustaining PLCs. The outcome of this project study was a professional-development model that will provide knowledge and understanding of the key leadership elements needed to develop an environment for sustaining PLCs. The potential social impact of this study includes improved student achievement as a result of improved leadership by principals.