Instructional coaches support teacher professional improvement and subsequent student learning through their instructional leadership; however, individual interpretations of district-wide instructional goals influence the work each instructional coach carries out at different school sites. This leads to a lack of systemic focus to ensure the work of instructional coaches is moving all teachers in a district, regardless of school site, towards coherent and sustainable instructional reform. The purpose of this study was to describe how three levels of instructional leaders-- district leaders, school site administrators, and instructional coaches--collaborated; additionally, the study aimed to identify how that collaboration benefited the work of secondary instructional coaches. Participants of the case study included two district level leaders, two administrators, and three instructional coaches from a medium-sized public school district in the Southwest United States. The participants' perspectives were gathered through semi-structured interviews, focus groups, and documents relevant to their collaborative efforts. The findings from this study supported prior literature regarding the benefits of collaboration and the role definitions of instructional coaches for effective professional development district-wide. Additionally, the findings differentiate between collaborative and professional learning as it connects to the social learning theories of Sensemaking and Communities of Practice and to the practical framework of PLCs at Work®. Unique findings from this study answers the research questions (RQ): RQ1: How do district leaders, site administrators, and ICs collaborate? RQ2: How does collaboration amongst the instructional leaders support the work of ICs? First, the findings described how the instructional coaches initiated, established the contexts, and led the collaboration sessions despite being lower in the positional hierarchy of those who participated. Additionally, there were unique findings explaining how the collaboration between district leaders, site administrators, and instructional coaches supported and benefited the work of instructional coaches: (1) a recognized value and need for the instructional coach voice; (2) professional learning was perceived as collective dialogue that led to common understanding of the instructional coaches' work, identification of obstacles that hindered that work, and proposing solutions to overcome those obstacles; and (3) clear and agreed upon goals, systemic accountability, and methods of assessment based in concrete products and visible actions were viewed as prerequisites for effective collaborative learning. [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.]