The focus of this work is interpersonal trust, by which I mean trust between individual persons. This work formulates and defends an account of interpersonal trust as an affective attitude, the presence and quality of which has significant ethical and social-political consequences. A major task of the dissertation is to dispel the assumption common to the majority of writings on trust that trust is a mere fail-safe social mechanism which, in a world of perfectly omniscient, or perfectly moral beings, would not be needed. I will argue that a philosophical accounting of trust is both possible and desirable, but that it can only be given in the context of an ethical approach that recognizes the importance of affect, character, and relationship...