Abstract: This article reviews the brain of ants in the context of their behavior. Division of labor underlies the social lifestyle of ants;it results not only in behavioral specialization, but also in some adaptations of ant brains. The structure and function ofmajor brain neuropils is described (visual and olfactory centers and central multi-sensory integrative brain compartments)together with some of their neurons. Unlike social vertebrates, which have larger brains and cerebral cortices than solitary species, ant brains are not bigger than those of solitary insects, but they are more specialized. The biological success of ants is probably not so much the result of an individual's brain as of the concerted action of a colony's hundredsor thousands of brains.