Why are people trustworthy? I argue for two theses. First, we cannot explain many socially important forms of trustworthiness solely in terms of the instrumentally rational seeking of one’s interests, in response to external sanctions or rewards. A richer psychology is required. So, second, possession of moral character is a plausible explanation of some socially important instances when people are trustworthy. I defend this conclusion against the influential account of trust as ‘encapsulated interest’, given by Russell Hardin, on which most (...) trustworthiness is explained by the interest of continuing relationship. (shrink)