Taking seriously the social dimensions of knowledge puts pressure on the assumption that epistemic agents can usefully be thought of as autonomous, interchangeable individuals, capable, insofar as they are rational and objective, of transcending the specificities of personal history, experience, and context. If this idealization is abandoned as the point of departure for epistemic inquiry, then differences among situated knowers come sharply into focus. These include differences in cognitive capacity, experience, and expertise; in access to information and the heuristics that make it intelligible; and in motivating interests and orienting standpoint. Dissent takes on rather different significance, as a potentially productive feature of epistemic life rather than evidence of a failure of aperspectivality or an indication of error. The central questions are, then, what forms of diversity are epistemically consequential, and how can they best be deployed to ensure that the beliefs we warrant as knowledge are as well grounded and truth-tracking as possible.