This case study focused on five Instructional Coaches working in public high schools. The intent of this study was to determine how these Coaches support the adult development of teachers. Three themes emerged from this study: 1) ambiguity regarding the role of Instructional Coaches impacts the performance of Coaches and the adult learners they support, 2) Instructional Coaches struggle to balance the work of supporting adult learners with tasks unrelated to supporting adult learners, and 3) preparation and ongoing professional development for Instructional Coaches is inconsistent in content and frequency. [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.]