Recent and ongoing expansion of online opportunities for teacher education and training continue in response to calls for better teacher preparation and professional development opportunities. However, with the introduction of online learning, the already controversial debate over educational technology has taken on a new dimension. Today's emerging challenge is the need to assess a different set of teaching and learning methodology that are specific to the content being delivered and the technology being used. This study employs the community of inquiry framework as a tool for evaluating deep learning by examining the social, cognitive, and teaching presence in an online learning environment. In addition, this study examines students' and instructors' perceptions of strengths, weaknesses, characteristics of successful participants, and effective components in an online TESOL teacher education program. Results indicate that students and instructors are generally satisfied with the program, despite the challenges they encounter with technological glitches. This study also found that characteristics of successful participants could be categorized into three themes--personality, skills, and learning or teaching styles. Finally, results confirm the importance of effective pedagogical features that aid in content creation and delivery, communication and collaboration, as well as tools for learning, assessment, and administration. These results point to implications for developing a community of inquiry in an online environment and areas for future research. [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.]