This study explores how teachers narrate and develop their identities through their participation in an online video study group. Participants are six public school world language teachers using "Teaching Proficiency through Reading and Storytelling" (TPRS) methodology who live in geographically diverse regions of the United States but work together by means of an online interface to present, watch and discuss video excerpts of each other's teaching. The identity construct employed in the study is grounded in the socio-cultural framework which holds that identity is developed through interaction and foregrounds the importance of narratives in arranging and restructuring teachers' identities. The study employs Bamberg's positioning analysis (Bamberg, 2004) to understand the narrative positioning moves made between group members together with a Bakhtinian dialogical framework to interpret how the interactions between group members over a period of several months work to both constitute their social environments and are in turn influenced by them. Particular emphasis is given to Bakhtin's construct of "ideological becoming" to identify the ways in which teachers use discourse to organize their teaching practices, group interactions and directions for future growth (Bakhtin & Holquist, 1981; Bakhtin, Holquist, & Emerson, 1986). Research findings of the study include a better understanding of the ways in which narrative is used as a tool to accomplish interactive goals and establish identity, as well as an increased understanding of the ways in which familiarity with common discursive communities both enables and constrains group interaction. The study additionally notes the lack of current research on online video study groups to support in-service teacher professional development and considers the impact of increasing such initiatives on teacher development. [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.]