Many of the most important social institutions—e.g., law and language—are thought to be normative in some sense. And philosophers have been puzzled by how this normativity can be explained in terms of the social, descriptive states of affairs that presumably constitute them. This paper attempts to solve this sort of puzzle by considering a simpler and less contentious normative social practice: table manners. Once we are clear on the exact sense in which a practice is normative, we see that some practices can be normative in an interesting and non-trivial sense, but also explicable with merely descriptive resources. In addition to arguing that it is possible to explain normative practices with descriptive resources, this paper presents and defends just such an explanation—an account of the nature of table manners that appeals only to descriptive states of affairs.