Insect neuropeptides are involved in most physiological processes in insects, such as diuresis, ecdysis, and pheromone biosynthesis. The peptides perform these functions as ligands for G-protein coupled receptors (GPCRs) that trigger specific biochemical functions. Our research in this area has focused on the Pheromone Biosynthesis Activating Neuropeptide (PBAN) and its GPCR in fire ants. I will show that PBAN is involved in fire ant pheromone production and interestingly, also in important functions of all colony life stages. Since many neuropeptides play critical roles in insect development and reproduction, the peptide hormones and their receptors are viewed as promising targets for novel biologically-based control. These possibilities will be illustrated. Secondly, the use of venom alkaloids, cuticular hydrocarbons, and pheromones as useful taxonomic characters will be illustrated using Solenopsis species in the USA and in South America.