This study was an inquiry into the influence of action research on teachers' practice and an exploration of the idea that teaching is synonymous with learning. After 14 participants engaged in individual action research projects that were facilitated by the researcher, the qualitative method of narrative inquiry was used to gather data from the participants. Throughout an intensive experience of action research, the researcher and participants reflected on the ways in which their perceptions of their craft and their learning were influenced. The participants were selected from the graduate students in the Leadership in Mathematics Education program and the teachers in the School for Children at Bank Street College of Education. The findings showed that teachers accepted their own research as an essential element in developing their own practice. They concluded that a purposeful way to approach professional development is to begin with the knowledge they possess from their experiences in their classrooms and their collaborations with colleagues. The teachers and graduate students were interested in exploring ways in which action research could become a sustained approach to professional development in their schools and most of the participants agreed that action research would be worthwhile in the pursuit of seeing teaching as a learning endeavor. However, in order for action research to be naturally integrated into the work of teachers, a consideration of the way a teacher's time is used would need to be mindfully discussed. [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.]