There is a dispute as to what sort of entity non-substantial individuals are in Aristotle's Categories. The traditional interpretation holds that non-substantial individuals are individual qualities, quantities, etc. For example, Socrates' white is an individual quality belonging to him alone, numerically distinct from (though possibly specifically identical with) other individual colors. I will refer to these sorts of entities as 'individual instances.' The new interpretation1 suggests instead that non-substantial individuals are atomic species such as a specific shade of white that is indivisible into more specific shades. On this view, non-substantial individuals are what we would call universals2 which can be present in different individual substances, but are labelled 'individuals' by Aristotle because, like individual substances, there is nothing they are said of.3 In this paper I will defend the traditional account by attempting to show that it is supported by the slender textual evidence that is available. I will begin by stating three serious objections to the traditional interpretation. Next I will show that in works later than the Categories Aristotle accepted individual instances of properties of the sort found in the Categories by the traditional interpretation. Finally, I will set out the evidence that supports the traditional interpretation and answer the three objections.