WAC scholars have demonstrated a strong commitment to faculty professional development in WAC programs but have yet to engage in much conversation, at least in scholarly literature, about the training of TAs in the teaching of writing. The rising number of TAs in doctoral-granting institutions and WAC programs suggests their role in teaching undergraduates how to write effectively is becoming more important and more prevalent, and because these TAs, like WAC faculty, engage in multiple interactions with student writers, they should also be considered teachers of writing. This article explores the history of TAs in WAC programs and several reasons why TAs have been virtually ignored in WAC discussions, arguing that WAC scholars must now turn their attention to disciplinary TAs, engage in discussion about the role of TAs in the teaching of writing, and develop WAC TA professional development programs.