The "No Child Left Behind Act" has profoundly impacted public schools throughout our country. All school personnel must work together thoughtfully and diligently to address the mandates set forth by this federal law. As reforms are initiated and instructional programs are restructured, this qualitative multiple-case study examines supervisory practices utilized in four elementary schools in South Western Pennsylvania and how these practices influence organizational learning. A qualitative method was chosen because it provides a more in-depth and interpersonal response to the research questions. Multiple cases were selected to increase the possibility that the findings may be further generalized. This study was grounded in theories of supervision and organizational learning. All four of the participating elementary schools were using the Walkthrough Observation Tool developed through the Principals Academy of Western Pennsylvania at the University of Pittsburgh. Information gathered from Walkthrough Observations was then analyzed and categorized into Blankstein's (2010) framework of six principles that synthesized research on Professional Learning Communities (PLCs). Of the four schools chosen for this study, two of them are participants of Educational Leadership Initiative (ELI). ELI is a systems approach to improve teaching and learning by bringing together superintendents, principals, and teacher leaders together to share a common vision, focus and goals. Individual interviews with superintendents and principals as well as teacher focus groups were used to gather information for this study. As presented in this study, superintendents and principals can effectively learn how to use walkthrough observations to positively promote professional learning communities within their schools. Both of these practices working separately are highly effective. However, when purposefully aligned, they are very powerful tools that may lead to or suggest an increase in student achievement within the schools. [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.]