While there is now considerable anxiety about whether the psychological theory presupposed by virtue ethics is empirically sustainable, analogous issues have received little attention in the virtue epistemology literature. This paper argues that virtue epistemology encounters challenges reminiscent of those recently encountered by virtue ethics: just as seemingly trivial variation in context provokes unsettling variation in patterns of moral behavior, trivial variation in context elicits unsettling variation in patterns of cognitive functioning. Insofar as reliability is a condition on epistemic virtue, we have reason to doubt that human beings possess the cognitive materials required for epistemic virtue, and thereby reason to think that virtue epistemology is threatened by skepticism. We conclude that while virtue epistemology has resources for addressing this challenge, exploiting these resources forces tradeoffs between empirical and normative adequacy.