The social science literature abounds with unconnected and, so it seems, diverse propositions about the emergence of norms. This article sets out to show that many of these propositions only differ in regard to terminology. Proponents of different theoretical orientations seem to accept a key hypothesis that is called “instrumentality proposition”: norms emerge if they are instrumental for attaining the goals of a group of actors. Apart from a problematic functionalist version the article focuses on an individualistic version: if actors (...) want to achieve certain goals and if a norm is instrumental to attain these goals individuals perform those actions that bring about the norm. This proposition involves several assumptions that are discussed.This version of the instrumentality proposition explains norms that are planned (i.e., that are second-order public goods). In order to account for the evolutionary emergence of norms a second version of the instrumentality proposition is discussed. It assumes that actors do not want to create a general norm but aim at providing certain private goods in interaction situations. For example, smokers sanction non-smokers in order not to be exposed to smoke in the interaction situation, but non-smokers do not want to engender a general non-smoking-norm. However, the aggregated effect of those actions is often a general norm.The article further explores problems of the two instrumentality propositions, the extent to which they answer important questions of a theory of norm emergence and alternative propositions to explain norms. (shrink)