For many contemporary liberal political philosophers the appropriate response to the facts of pluralism is the requirement of public reasonableness, namely that individuals should be able to offer to their fellow citizens reasons for their political actions that can generally be accepted.This article finds wanting two possible arguments for such a requirement: one from a liberal principle of legitimacy and the other from a natural duty of political civility. A respect in which conversational restraint in the face of political agreement involves incivility is sketched.The proceduralist view which commends substantive disagreement within agreement on procedures is briefly outlined, as is the possible role for civic virtue on this view.