Several decades of work in both philosophy and psychology acutely highlights our limitations as individual inquirers. One way to recognize these limitations is to defer to experts: roughly, to form one’s beliefs on the basis of expert testimony. Yet, as has become salient in the age of Brexit, Trumpist politics, and climate change denial, people are often mistrustful of experts, and unwilling to defer to them. It’s a trope of highbrow public discourse that this unwillingness is a serious pathology. But (...) to what extent is this trope accurate? Answering this requires us to settle both a normative question—under exactly what conditions ought we to defer to experts?—and an empirical question—under what conditions are people willing to defer to experts? The first question has been investigated primarily by philosophers; the second, primarily by psychologists. Yet there is little work integrating these literatures and putting together their results. The aim of this review article is to begin this task, enabling us to begin reaching conclusions about how much real practices of deference diverge from the ideal. We present an opinionated guide to relevant work from both philosophy and psychology, and note places where the literature has important gaps. (shrink)