There are two ways in which the social ideal of equality has found expression in the law: in the principle of equal treatment and in the principle of non-discrimination. In this article the meaning of these two legal principles is analysed, in order to answer the question to what extent they can be said to contribute to equality in the sense of an equal distribution of collective resources. It is argued that whereas the first just requires decision-making to be rule-based, the second principle demands that rules should be based on sound categorical distinctions. Neither of the two can, however, sensibly be linked to equality as equal distribution. The article concludes that the only way to establish such a link is by adding to the principle...