The purpose of this study was to investigate six preservice teachers' understandings of the theory and practice of teaching and learning foreign languages during their course work and field experiences in a teacher education program. The participants in the study were full-time students in a year-long graduate-level program. This paper focuses on the participants' understandings of how to teach in a particular classroom context. Ethnographic techniques, including observations, interviews, and document analyses, were used. In discussions of how to teach a foreign language, the participants outlined the need for teachers to provide a language-rich environment in which students are guided to use the foreign language to express themselves and obtain information from others. Methods courses supported these ideas. However, during the participants' field experiences, contextual constraints entered into the equation, and many opted to abandon these practices when they encountered a negative reaction from their students and mentors. Although teacher educators have an opportunity to ground preservice teachers in the theory and practice of foreign language education in methods courses, they should recognize that corresponding field experiences seldom represent idealized language learning situations. Despite a base of foreign language pedagogical content knowledge, what preservice teachers really need is continued support in order to learn to adapt their teaching methods to whatever circumstances they encounter. (Contains 33 references.) (KFT)