The purpose of this descriptive study was be to determine if there were differences in the implementation of professional learning communities components between elementary and secondary teachers and administrators. This study examined the relationship between demographic characteristics and teacher implementation of professional learning communities components. The study also examined the impact of teachers' perceptions of efficacy based on their involvement in professional learning communities and determined if this involvement impacted their self-efficacy in a positive or negative manner. The implementation of professional learning communities components by principals and assistant principals were also examined. This study focused on a SA public school district in north Texas that implemented professional learning communities components for six years. Random selection was used to create a sample of 200 elementary teachers and 200 secondary teachers from the selected school district. The participants were asked to take the professional learning communities Survey and Teachers' Sense of Efficacy Scale. The 41 campus-level principals and assistant principals were asked to take the Professional Learning Communities Survey in order to make comparisons with the teachers' responses. This study used a series of multivariate analyses of variance and a multiple regression to address the research questions and to look for significant differences. The results of the study showed that differences did exist between elementary and secondary teachers in the implementation of professional learning communities components and perceptions of self-efficacy. The multiple regression showed that the participant's score on the Professional Learning Communities Survey was a good predictor for the participant's score on the Teachers Sense of Efficacy Scale. Differences also existed between teachers and administrators in the implementation of professional learning communities components. The conclusions stated that differences between elementary and secondary teachers could be explained by structural differences, and when professional learning communities are operated effectively, the differences are minimized. The significance of this study was to help teachers and administrators understand the professional learning communities components that exist within elementary and secondary schools. This study would add to the existing body of research on professional learning communities and help educators create better learning environments for all students. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]