One model that has evolved as a way of supporting this paradigm change is that of professional learning communities (PLCs). Although, current professional development literature is replete with articles that extol the virtues of learning communities as an essential way to organize schools in order to maximize time spent in professional development (e.g. Bryk, Lee, & Holland, 1993; Louis & Marks, 1998), only recently has the focus of this literature shifted to examining empirically the changes in teachers’ practices and students’ learning as a result of PLCs. Although, teachers’ perceptions about the value of PLCs are both valid and valuable, understanding the outcomes of these endeavors on teaching practice and student learning is crucial, particularly in today’s era of scarce resources and accountability. With this in mind, the purpose of this manuscript is to provide a review of the research available on the impact of PLCs on teaching practices and student learning. In an attempt to create a comprehensive picture we first provide an overview of the essential characteristics of PLCs. After developing this foundation, we examine the current literature as it relates to two basic questions: