In recent decades, a growing interest in studies of teacher identity in the field of English as a second language (ESL) teacher education research has developed. In order to better understand issues in teacher education, researchers need to explore how teacher identities are developed through the negotiations of their experiences. This study frames teacher identity development based on Dewey's philosophy of education and experience and other identity research, aiming to provide a more comprehensive understanding of the interplays between teachers' multilevel experiences and professional identity development. Using identity as a tool to analyze teachers' stories provides additional lenses to understand the interactions between teachers' inner selves and external worlds across time and space.The findings of three non-native English-speaking (NNES) ESL teachers' stories highlighted three dimensions -- temporality, sociality, and rationality -- in the complex process of teacher identity development. The temporal dimension helps to understand a teacher's present and imagined identities through exploring their past experiences. In addition, the three teachers' stories highlighted the ways in which their imagined identities created motivation to actively engage with professional growth to become the teachers they desire or are expected to be. The teachers' stories about the rewarding moments demonstrated how their career commitment was enhanced by positive teaching experiences. Moreover, the findings suggest that teachers' transcultural and transnational educational and teaching experiences can create both constraints and affordances for their professional identity development. The three participating teachers' stories showcased that their negotiations of experiences and active positioning of selves were at the core of teacher identity development. The findings of this study offer suggestions for teacher educators working with teachers from diverse backgrounds and provide future directions for teacher education researchers to further support the development of teacher identity. I offer new ways of interpreting identity for teacher educators and teacher identity researchers. [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.]