Professional learning communities (PLCs) have gained attention as an effective practice for supporting teachers and developing students since their inception in the early 1990s yet there is still work to be done in developing a blueprint for effective implementation in a pervasive culture of isolation and resistance, especially in secondary schools. While there is political, scholarly and practitioner interest in PLCs as a reform, few empirical studies explore the leadership implications of implementation. The purpose of this qualitative phenomenological study was to investigate the lived experience of 6 secondary site leaders in the Southern California region as related to the implementing and sustainment PLCs at their sites. The purpose of this study was to glean the significant challenges and barriers faced by these sites as well as the effective strategies and tools to overcome those challenges as evidenced through the analysis and coding of 1-on-1 in-depth interviews with carefully selected PLC leaders. 9 themes emerged during the analysis. There were 6 themes under Research Question # 1: (a) PLC steps were implemented to address low API scores, (b) lack of communication and collaboration prior to PLC implementation, (c) resources of time and money, (d) overcoming staff resistance, (e) the importance of a Leadership Team, and (f) building relationships. There were 3 themes under Research Question # 2: (a) facilitating ongoing communication and celebration, (b) using professional development to promote PLC work, and (c) using common practices for PLCs. The study's findings suggest recommendation of several leadership strategies and resources that secondary site leaders should consider when implementing PLCs at their own sites. [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.]