Communication between principals and music teachers is an important aspect of music's role in the school and education. Understanding the process of communication, including elements such as content and methods, could provide valuable insight to improve working relationships and positively affect many aspects of the school. Specifically, for music teachers, effective communication with principals has resulted in less conflict and more understanding and cooperation between the music teacher and principal. The purpose of this study was to develop a theoretical model of the communication process between secondary school principals and music teachers. In order to investigate these research questions and fulfill the purpose of the study, grounded theory research methodology was utilized to study the process of communication between secondary school principals and music teachers. The themes that emerged through data analysis were formal and informal communication, trust, working relationship, the process of communication, methods of communication, barriers, and effective communication. The grounded theory model was then constructed and included several interconnected facets. The contextual conditions were school requirements and climate, which surround the other aspects of the theory. The intervening conditions were personality, trust, informal relationship, clarity, and shared understanding. Method and frequency of communication were the actions and interactions in the grounded theory. The outcomes of the communication process were clear and shared expectations and program support. The grounded theory indicates that the intervening conditions affect the actions and interactions, which led to the outcomes of the communication process. The working relationship was the central phenomenon as well as a separate, but intertwined aspect of the theory that affected and was affected by the other facets. The theoretical model may help those involved understand the factors that contribute to communication as well as the outcomes of effective communication so that they may use it more effectively to elicit positive outcomes, including working relationships. With more communication knowledge, tools, and strategies, principals and teachers can improve their working relationships with each other and positively impact the school climate and culture as well as student achievement. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]