Pheromones have essential roles in the social behavior of most animals. Studies of pheromone-driven behaviors are especially attractive in Drosophila melanogaster, because these insects are genetically and molecularly well characterized, have relatively simple central nervous systems compared with vertebrates, and yet they display complex behaviors controlled by sophisticated sensory systems. Like most other aspects of biology, studies on pheromone-driven behaviors have entered a new area, as candidate pheromone receptors and signaling molecules have been identified through the deciphering of the Drosophila genome. These advances have made it possible to make specific manipulations of pheromone pathways for further investigation.