This chapter argues that friendship is a theme central to a trilogy of dialogues, the Theaetetus, the Sophist, and the Statesman, and that highlighting this theme helps bring into clearer focus an ethical and political dimension of these dialogues that is commonly overlooked or ignored in the scholarly literature. More precisely the chapter aims to demonstrate that the theme of friendship amplifies the ethical and political implications of the inquiries into sophistry, political expertise, and knowledge central to the trilogy. I argue that friendship becomes a theme because philosophy is set apart from sophistry and political expertise in the dialogues in part through the different ways in which philosopher, sophist, and statesman are described as interacting with their fellow human beings, interactions that can best be described in terms of friendship or lack thereof. These differences are articulated both through the dialogues’ analysis of sophistry and political expertise and through the drama of the dialogues. This drama revolves in part around the question whether Socratic philosophy is a kind of sophistry as well as a prolonged attempt to turn Theaetetus and Theodorus away from sophistry and to help them advance beyond mathematics toward philosophy.