Professional Learning Communities (PLCs) provide the best setting for building collective teacher efficacy (CTE). CTE has been identified as having the highest positive effect on student achievement. The purpose of this qualitative study was to explore perceptions of teachers and administrators regarding the effectiveness of PLCs for building collective teacher efficacy. This study sought to pinpoint the barriers for effective implementation of PLCs, analyze the importance of CTE in the PLC process, and identify research-based practices for effective implementation of PLCs. This study is significant because facilitating implementation of effective PLCs that build CTE can lead to enhanced teacher practices and improved student achievement. Adult Learning Theory, Social Cognitive Learning Theory, and Collective Teacher Efficacy provided the theoretical framework and framed the research questions that guided this investigation. Through the study's design, data was collected through surveys. The findings of this study may be beneficial to teachers and administrators who are seeking implementation of effective PLCs and developing CTE to enhance teacher practice and improve student achievement. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]