This qualitative case study explores how collaborative teacher research serves as a professional development model for practicing teachers. The purpose of the study is to examine how participation in a collaborative teacher research group affected three French teachers' understandings of one state's foreign language standards, and to look at how those understandings were realized in a collaborative teacher research (CTR) project. This article specifically focuses on the results emanating from how the three French teachers individually and collaboratively interpreted and implemented foreign language standards while participating in CTR. Data were collected from workshops, journal entries, classroom observations, lesson plans and materials, workshop evaluations, the teachers' research, and email conversations. Results show that the teachers learned about the standards primarily from collaborating with their students. (Contains 2 notes.)