Mating behavior is fundamental to survival and propagation of a species. Despite its centrality to reproductive success, how the mammalian brain generates this primal behavior has been elusive. We have employed recent advances in deep sequencing and brain mapping in mice to define a neural circuit that transforms sensory information into motor components of mating. This neural pathway spans multiple synapses, and it encodes the key elements of male sexual behavior: it is developmentally wired, it recognizes potential mates, it is male-specific, and it governs mating displays, libido, and the hedonic aspects of this behavior. I will describe these and other unpublished findings from my group.