One of the main challenges in the philosophy of language is determining the form of knowledge of the rules of language. Michael Dummett has put forth the view that knowledge of the rules of language is a kind of implicit knowledge; some philosophers have mistakenly conceived of this type of knowledge as a kind of knowledge-that . In a recent paper in this journal, Patricia Hanna argues against Dummett’s knowledge-that view and proposes instead a knowledge-how view in which knowledge of the rules of language is a kind of practical knowledge, like an agent’s non-propositional knowledge of counting. In this paper I argue, first, that Hanna misunderstands Dummett’s conception of knowledge of linguistic rules, and, second, that Dummett’s considerations of practical knowledge of language pose a problem for Hanna’s knowledge-how view. At the end of the paper, I briefly sketch an account of practical knowledge of language that meets the requirements set by Dummett.