There is evidence that Extreme Programming (XP) software development practices are still actively used by Information Technology (IT) projects under the Agile methodology, one of the famous software development life cycle (SDLC) models. However, more information about the communication between programmers or developers for these XP practices is needed. Thus, this study, employing a constructivist grounded theory (CGT) design which emphasizes the construction of knowledge through the interpretation of data, was conducted to explore developer communication for significant XP practices. For the initial data, the researcher was fortunate to have the participation of eleven out of fifteen IT professionals, each with at least a decade of work experience. Their expertise was invaluable in shaping the direction of the research. Three out of four identified developers also participated in a follow-up questionnaire. Subsequently, semi-structured key informant interviews were conducted, focusing on their top three practices: Planning Game, Test-Driven Development (TDD), and Small Releases, which were selected based on their perceived importance in IT projects. During the interviews, it became evident that the developers play multiple roles, each significantly influencing communication. These fourteen identified roles highlight their work’s diverse and complex nature: Assessor, Collaborator, Coordinator, Designer, Developer, Documenter, Interpreter, Learner, Mentor, Negotiator, Presenter, Researcher, Tester, and Translator. The developers interacted with seven teams categorized into four groups based on their modes of communication: Direct Managers and Change management under Linear-Interactional, Business Team under Interactional, External Developers, Functional Resources, and Technical Team under Interactional-Transactional, and Transactional-Interactional for Internal Developers. With all the combined practices, roles, and interactions, this study has proposed an XP Developer Communication (XPDC) model. This framework can serve as a guide for understanding and improving developer communication in XP projects. For instance, it can help identify the key roles and their communication needs or guide the selection of appropriate communication modes for different teams. Although not all XP practices are covered, the components are enough to cover all the essential developer communication practices in XP.