The purpose of this qualitative study was to explore the leadership practices of principals who sustain professional learning communities. The study was conducted using semistructured interviews with 2 elementary school principals from a noted professional learning community district in Henderson, Kentucky. A Professional Learning Community Assessment Survey was completed by the teachers in both elementary schools. Photographs of each school and a review of school documents triangulated the research of these 2 professional learning communities. In interviews the principals described their roles in: (1) defining a professional learning community or PLC, (2) supporting and sustaining a PLC, (3) supporting professional dialogue opportunities in a PLC, and (4) identifying shareholders as an essential element in successful professional learning communities. The teacher surveys helped to confirm the principals' perceptions and the roles of the principals in supporting and sustaining a professional learning community. The teachers defined the principal's role in supporting and sustaining a professional learning community as (1) involving staff in decisions, (2) incorporating teachers' advice to make decisions, (3) providing staff members access to key information, (4) the principal being proactive, (5) enabling staff members to initiate change, (6) sharing responsibility and rewards, (7) sharing power and authority, and (8) promoting and nurturing leadership. The effective leadership practices of both principals support successful and sustainable professional learning communities. The triangulation of data reinforced these conclusions: (1) both principals have effective leadership practices that support and sustain a PLC, (2) the majority of teachers from both schools who participated in the survey overwhelmingly approve of the leadership practices of their principals, (3) continued improvement in student assessment results over a period of years support the practices of the principals, and (4) effective leadership practices strengthen the professional learning concept of supporting and encouraging continued student and teacher progress. The results from this study were intended as a reference for principals and school districts concerning the effective practices of principals to support and sustain professional learning communities.