This dissertation argues that contemporary scholarship in the field of composition and rhetoric largely marginalizes and misconstrues the work of Ann Berthoff, one of the field’s founders. Employing a feminist rhetorical, dialogic methodology, my study resources the scholarship of Ann Berthoff, the newly available archival collection of her papers, a personal interview with Berthoff, and a survey of contemporary and historical texts in the field that enroll Berthoff into their discussions. I enroll these sources in order to identify, trace the origins of, and explain the misconstruance of Berthoff’s work. This work suggests that the field pays a price in continuing to get Berthoff wrong: underlying the ebb and flow of calls for disciplinarity in the field of comp/rhet is the inadequacy of postmodern theories of language to account for the field’s value and identity. If the field is going to break free from mere discussion of disciplinarity, it needs to reckon with the work of Ann Berthoff and fully account for her theory of language, Peircean triadicity.