The term professional learning community is generally defined as a group of people sharing and critically interrogating their practice in an “ongoing, reflective, collaborative, inclusive, learning-oriented, growth-promoting way and operating as a collective enterprise” (Stoll, Bolam, McMahon, Wallace & Thomas, 2006, p. 223). The professional learning community is increasingly being used as an explicit change strategy for generating, sharing and managing knowledge in educational organizations. Improving the performance of a district requires district supervisory officers to build their capacity for learning how to improve leadership practices. In this retrospective qualitative study, I investigate to what extent leadership practices change for a group of district supervisory officers, that is, the senior leaders responsible for the district leadership functions, while they responded to provincial reform mandates between 2000 and 2006. I also examine whether this group of supervisory officers in one Ontario English Public School District, renamed Green Ridge District School Board (GRDSB) for anonymity, functions as a professional learning community. Data sources used in this investigation were developed through a university partnership between GRDSB and an Ontario Institute for Studies in Education field center known as the Midwestern Centre. Data were gathered from six research reports, written annually between 2001 and 2006; interviews from seven supervisory officers conducted in 2006; and interviews from 12 school administrator interviews held in 2005. One limitation of the study is that participants were selected from school sites that chose to become involved with the district change strategies and therefore tended to take a positive orientation when responding to semi-structured questions. The data gathered did not reflect the views of those who chose not to be actively involved in the district change strategies. This investigation’s findings inform leadership theory and practice with respect to the descriptions of evolving leadership practices of a group of supervisory officers as they worked to re-culture the GRDSB. Findings provide empirical support for the contention that a socially constructed environment, such as a professional learning community, provides a context for supporting changes to leadership practices through collective professional learning, problem solving, knowledge creation and knowledge sharing (Anderson, 2006; Honig, 2008; Louis, 2008).