This paper defends a moralized account of conventions, according to which conventional practices are necessarily normative reasons that are ultimately grounded on moral principles . It argues that a convention exists just in case the fact that others participate in some common practice as well as facts about their motivating reasons for doing so, justify conformity to that practice. The paper locates this moralized account within the relevant philosophical literature and argues that it does better than its rivals in explaining (...) the presence of both motivating and normative reasons in our concept of convention. (shrink)