The 1985 Research Conference on Fire Ants and Leaf-Cutting Ants covered the most recent developments in research and control of these insect pests of the New World tropical and subtropical zones, the southern United States, South and Central America, and the Caribbean Islands. This volume contains chapters that discuss the history and economics, biology and ecology, behavior, pheromones and other semiochemicals, physiology, and biochemistry of fire ants and leaf-cutting ants, as well as current and future control strategies. The information provided illustrates past and present agricultural and medical problems associated with these pest ants; however, it also brings out the point that they may at times be beneficial. The chapters on basic aspects of the biology and ecology of the ants provide up-to-date information that is useful for a more complete understanding of their social behavior and the unique symbiotic relationship between leaf-cutting ants and their fungi. New approaches to control are illustrated by innovative research on anti-feedant chemicals from plants that prevent feeding by leaf-cutting ants. The present status of chemical baits and biocontrol is addressed, as well as the possibilities of future novel methods based on the use of anti-metabolites, insect hormones, behavior modifying substances, and species-specific toxic bait systems to create integrated pest management systems.