Instructional coaching is one method of job-embedded professional development approach that provides teachers an opportunity to build teacher expertise, raise student achievement, and advance school reform. The problem that was addressed in this qualitative case study was that few principals' understand the process of instructional coaching as job-embedded professional development to improve teacher practice, which plays a pivotal role in the success of the implementation of instructional coaching as job-embedded professional development. The purpose of this qualitative case study documented and analyzed elementary school principals' understanding and implementation of instructional coaching as job-embedded professional development. The purposive sample was comprised of K-5 elementary school principals from an urban school district that supported instructional coaching as job-embedded professional development. In-depth interviews were used to gather principals' perceptions of instructional coaching as job-embedded professional development. The results of this study reflected what principals' perceived as important factors necessary to implement and understand instructional coaching as job-embedded professional development. The results showed that many factors contributed to the implementation and understanding of instructional coaching in that principals need to put forth great effort in determining how to implement and understand instructional coaching in their schools. A majority of participants purported that knowing the school data and goals assisted in the implementation of coaching and a starting point critical for the onset of the implementation process. Principal's experience in coaching and training in instructional coaching also contributed to the implementation of instructional coaching. Participants verified the importance of understanding instructional coaching by having prior knowledge of coaching, knowing the relationships involved in instructional coaching, process of getting teacher buy-in, building teacher capacity, knowing the principals' role and purpose, understanding the impact on teacher practice by utilizing best practices, and promoting teacher leaders all contribute to the understanding of instructional coaching. Recommendation for future research would be to utilize a mixed method research strategy with a larger population of urban schools to obtain a greater amount of data. By adding a quantitative aspect to a future study can further add to the correlation of how instructional coaching affects student achievement in 21st century 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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]