Abstract
I will consider disagreement from a communal perspective. Thus, my focus will not primarily be on disagreement between different groups although this case will figure as well. My main focus is on the epistemic pros and cons of disagreement for a community and on how the social structure of the community bears on these pros and cons. A central lesson will be that disagreement has more epistemic costs at the communal level than is often recognized, and that these epistemic costs often yield epistemic injustice.