Ants are probably the most dominant insect group on Earth, representing ten to fifteen percent of animal biomass in terrestrial ecosystems. Flowering plants, meanwhile, owe their evolutionary success to an array of interspecific interactions--such as pollination, seed dispersal, and herbivory--that have helped to shape their great diversity. brings together findings from the scientific literature on the coevolution of ants and plants to provide a better understanding of the unparalleled success of these two remarkable groups, of interspecific interactions in general, and ultimately of terrestrial biological communities.