The current article offers a brief history of research and theory related to social categorization and stereotyping. We begin by outlining research focusing on category selection, category activation, and category application. We then discuss the consequences of social categorization, noting that one of the most important and ubiquitous effects of social categorization is homogenization or assimilation. We then extend this research related to the assimilative consequences of social categorization to the realm of face memory. Specifically, we introduce the Categorization-Individuation Model (see also Hugenberg et al., forthcoming) as a new model of the Cross-Race Effect, or the difficulty many perceivers have in recognizing members of other racial groups. The Categorization-Individuation Model argues that the Cross-Race Effect is due to the tendency to categorize out-group members but individuate in-group members. Finally, we summarize the extant research in support of this new model of person memory and close by discussing the current state of, and potential future directions for, social categorization research.