Nearly 30 years ago, Ron Edmonds identified the instructional leadership of principals as one of the characteristics of effective schools. The connections between what principals do as instructional leaders and the successes of their schools continue to be well recognized. Principals who comprehend the significance of these linkages, however, realize they cannot provide all the leadership necessary for their schools to work toward maximizing instructional potentials and outcomes. Professional learning communities (PLCs) have been recognized and used as viable means for consciously placing curricula, teaching, learning, and achievement at the center of schools. When PLCs are focused on those elements "there is an air of professionalism among all the teachers as they participate on effective learning teams and share basic norms and values relative to students." Principals have opportunities to play key roles in establishing the conditions within which PLCs can flourish. They can do this by creating the time for such dialogue to occur; they can enhance its effectiveness by purposefully developing and then supporting teachers' use of collegial conversations within PLCs.