The purpose of this study is to examine the teacher identity development of Teach for America (TFA) teachers in relation to English language learners (ELLs) in the context of a semester-long teaching English as a second language (TESL) course. In addition, this study aims to explore primary considerations come into play in TFA teachers' teacher identity development as novice teachers of ELLs. The theoretical lenses guiding this study are Wenger's Community of Practice perspective and Positioning theory (Davies & Harre, 1990). A multiple-case design is employed to examine TFA teachers' teacher identity in relation to ELLs. Data collection took place approximately six months and included individual interviews, focus group discussion, artifacts, field observations and researcher's journal. Findings indicated that the TESL course provided context for developing new understandings for the TFA teachers and contributed to their teacher identity through improving their knowledge of the education of ELLs. The TESL course also led to some positive changes in the TFA teachers' beliefs about the teaching of ELLs and enabled them to develop new understandings about working with ELLs as content-area teachers. However, the TESL course did not influence all five TFA teachers' positional identities as teachers of ELLs. The TFA teachers, except one, did not take on a linguistically responsive teacher perspective and charged bilingual or ESL teachers with the responsibility of educating ELLs. This study also found that the following five primary considerations influenced the trajectory of the five TFA teachers' professional development as novice teachers of ELLs: (a) decision to become a teacher, (b) school culture, (c) level of content area knowledge, (d) positionings in relation to ELLs, and (e) sources of support. These considerations facilitated or hindered the TFA teachers' teacher identity development process as novice teachers in the teaching community and played a role in their growth as teachers of ELLs. This study contributes to the literature by examining TFA teachers' teacher identity development in relation to ELLs and identifying primary considerations that influenced TFA teachers' teacher identities as novice teachers of ELLs. The findings of this study have implications for the TFA organization and teacher preparation courses on ELL instruction. [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.]