This article explores the necessary and jointly sufficient conditions for the recognition of a ground of unlawful discrimination. It is important not only to have a coherent understanding of the currently enumerated grounds, but also to have a theoretical framework that can assist in enumerating new grounds through the open-ended “other status” aspect of many legal frameworks. To that end, this article argues that personal characteristics that are generally morally irrelevant, and that are socially salient in that they carry with (...) them a prevalence of inequality-laden attitudes, amount to necessary and jointly sufficient conditions for recognizing a ground of unlawful discrimination. Other conditions, such as immutability and the presence of relative group disadvantage, will be assessed and dismissed as contingent but not necessary conditions. (shrink)