This dissertation studies the nature and meaning of friendship (philia) in the Platonic dialogues and argues for its central and pervasive importance to his political and philosophical thought, and traces how philia emerges as a political and philosophical problem. On the one hand, philia is grounded in and grounds the city. As an essential component of justice, the common good, and civic concord, philia inspires and demands political virtue. On the other hand, Plato describes another aspect of philia: friendship encompasses the intense, private benefits one human being can provide another in the common pursuit of wisdom. Thus philosophical friendship necessarily situates itself in a tense relation to political friendship. As this dissertation contends, however, Socratic friendship both manifests and attempts to mitigate this tension. After first tracing the emergence of these questions within the LysisÌ¢ âÂ" Plato's only dialogue specifically devoted to the question of philiaÌ¢ âÂ" the dissertations treat the theme of philia through an account of Socrates' relationship with Alcibiades, Crito and Callicles. The dissertation offers three arguments about Socratic friendship in the Platonic dialogues: a) Socratic friendship solicits, enables, and sustains philosophic dialogue and rewards the search for wisdom; b) Socratic friendship moderates the eros of the potential tyrant by offering a good both noble and pleasurable; and c) Socratic friendship sets the conditions for inverting the ethical matrix of the friend/enemy dichotomy dominant in ancient Greek political life.