This study explores the factors that contribute to Indonesian English language teachers' (ELTs) professional growth and identity formation. The main question investigated in this study is: What are the factors and challenges that contribute to Indonesian ELTs' professional growth and identity formation as reflected in their life histories, critical events, and identity claims? To address this question, three research questions are posed: (1) What are the major critical events and identity claims in their life histories which were pertinent in the ELTs' professional identity formation? And in what ways do the ELTs consider them pertinent? (2) What are the challenges encountered by the ELTs in the profession? (3) What do those challenges imply about how the Indonesian ELTs aspire to develop and fulfill their professional identities? The study comprised two stages: the autoethnography and narrative inquiry. The data for the autoethnography, in which I was both subject and researcher, were collected based on personal documents, notes and photos that evoked and enhanced my memories. In the narrative inquiry, I interviewed five Indonesian ELTs who were studying for their doctorates in two US universities in the Midwest. I also conducted focus group discussions in the two sites. The interviews and discussions were recorded and transcribed. I employed a sequential analysis, from episodic chronological construction of life histories, to analysis of identity claims and critical events (Gee, 2001; Riessman, 2008; Webster & Mertova, 2007). The framework to understand the ELTs' professional growth and identity formation was the Scope of Second Language Teacher Education (SLTE) as suggested by Freeman (2009). The results of this two stage study suggest various factors and challenges that influenced the Indonesian ELTs' professional growth and identity formation. Among these factors and challenges are the struggles with self-doubts, different routes to the profession, and the Indonesian context of the profession. These factors are important in determining the professional growth of the Indonesian ELTs as well as in enhancing their professional identity as English teachers at the university level. This study confirmed the strength of Freeman's (2009) framework. In the case of Indonesian ELTs, their professional growth and identity formation were marked by their engagement with what Freeman labelled as "substance" which consists of knowledge and skills, socio-professional participation, and social activism. [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/en-US/products/dissertations/individuals.shtml.]