In Frege Philosophy of Language Dummett was inclined to dismiss Frege's assimilation of concepts to functions as an unfortunate consequence of his mistaken assimilation of sentences to complex proper names. And although he later somewhat modified his assessment of the importance of the Fregean idea that concepts are functional, he continued to insist that concepts and functions are at best analogous, since truth-values are not objects. Here, Dummett's reasons for rejecting the assimilation of sentences with names are critically assessed, along with the consequent doubts which he casts on Frege's claim that concepts are best understood as functions. It is argued that this is a place where Dummett's interpretation of Frege is influenced by his early immersion in the philosophy of Wittgenstein, and that in virtue of the fact that he read Frege through the lens of Wittgenstein's attitudes Dummett failed to do justice to Frege's claim that concepts are literally functions.