Psychological-epistemic accounts take scientific progress to consist in the development of some psychological-epistemic attitude. Disagreements over what the relevant attitude is – true belief, knowledge, or understanding – divide proponents of thesemantic,epistemic,andnoeticaccounts of scientific progress, respectively. Proponents of all such accounts face a common challenge. On the face of it, only individuals have psychological attitudes. However, as I argue in what follows, increases in individual true belief, knowledge, and understanding are neither necessary nor sufficient for scientific progress. Rather than being (...) fatal to the semantic, epistemic, and noetic accounts, this objection shows that these accounts are most plausible when they take the psychological states relevant to scientific progress to be states of communities, rather than individuals. I draw on recent work in social epistemology to develop two ways in which communities can be the bearers of irreducible psychological-epistemic states. Each way yields a strategy by which proponents of one of the psychological-epistemic accounts might attempt to account for the social dimensions of scientific progress. While I present serious reasons for concern about the first strategy, I argue that the second strategy, at least, offers a promising path forward for a psychological-epistemic account of scientific progress. (shrink)