This article links the visual perception of faces and social behavior. We argue that the ways in which people visually encode others' faces — a rapid-fire perceptual categorization — can result in either humanizing or dehumanizing modes of perception. Our model suggests that these perceptual pathways channel subsequent social inferences and behavior. We focus on the construct of perceptual dehumanization, which involves a shift from configural to featural processing of human faces and, in turn, enables the infliction of harm, such as harsh punishments. We discuss visual attention as an antecedent of perceptual modes and consequent modes of social behavior and speculate about the functions of humanization and dehumanization in sustaining macro-level social structures.