The focus of this study was to explore high school teachers' perceptions of self-directed professional development learning as participants in a community of practice. The questions for this study were: How did directing their own learning influence high school teachers' perceptions of their professional development? How did participating in a community of practice influence high school teachers' perceptions of their professional development? Four teachers participated in a community of practice. Individual participants used practitioner inquiry to collect and to analyze data as appropriate to their classroom practice instructing the students. I was both a participant and a researcher in the study. In my role as participant, I too used practitioner inquiry to examine my professional practice and my experience in the community. My membership in the community of practice provided access to and perspective about participating teachers' experiences. The conceptual framework included sociocultural theory and social constructivism to explore theories of learning and culture in a community of practice. I utilized methods of interactional ethnography to investigate relationships between discourse, activities, and the participants' construction of knowledge. I examined video recordings, transcripts and written artifacts produced in the community of practice. I analyzed the participant's experiences from their words and descriptions with Spradley's Developmental Research Sequence. Using an interactional ethnographic perspective allowed me to examine how teachers constructed professional development individually and cooperatively as participants in a community of practice. Findings from this study suggest, among other things, that teachers individually constructed their own professional development utilizing practitioner inquiry to explore self-selected questions specific to their practice in the context of their work with support from the community. Practitioner inquiry was an individual process. Collaboration in a learning community enabled the teachers to construct their professional development connected to context of work. Findings from this research study contribute to an understanding how Situated Learning Theory connects to teacher professional development. Situated Learning Theory can explain how member participation in a learning community can prompt engagement and motivate 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.]