The USDA-ARS Southern Insect Management Research Unit has been conducting research over the past two years to measure benefits and costs of treating conventional and Bt cottons with Karate and Prevathon. These studies include large field cage experiments with extreme densities of bollworm and tobacco budworm, small plot replicated field studies at Stoneville, Mississippi, and large strip studies on production farms in the Mississippi Delta. Results vary with densities and species of the pest species infesting the cotton. Under high densities of bollworm that cause significant yield loss, there are benefits to spraying both conventional and Bt cottons. In situations with lower densities or infestations largely composed of tobacco budworm, there may be no economic benefit for spraying Bt cottons. More research is needed to document the probability of these outcomes. This presentation was developed in collaboration with Dr. Clint Allen and Dr. Ryan Jackson of USDA-ARS.