The purpose of this study was to expand on our present knowledge of teacher beliefs in general and particularly to investigate the relationship between teacher beliefs and the context in which teachers work. Specifically, the study addressed and expanded the role of context, which has been inadequately theorized in previous studies investigating teacher beliefs. The research design utilized a multiple case study format focusing on four, English as a Second Language (ESL) classrooms in two community colleges over the course of a 16-week semester. Focusing on the experiences of four ESL teachers, I examined their beliefs about teaching and learning and the context in which they occurred using socio-cultural activity theory as a framework for analysis. The results showed that common conceptual terms used to describe teachers beliefs about teaching and learning were appropriated from a larger theoretical discourse on language teaching and learning. Shared concepts were incorporated into departmental models and approaches to teaching practice, influencing teacher's ways of thinking about the activity of teaching and learning. The meanings of collective concepts were also transformed as they were internalized by the teacher subjects and used to mediate classroom actions and operations within context. The results of the study imply that context has a significant effect on the formation and transformation of teacher's beliefs about teaching and learning. [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.]