In the 1996/97 season the Australian industry adopted an insect-resistant variety of cotton (INGARD) that is specific to the group of insects including the target pests Helicoverpa armigera and H. punctigera but excluding natural predators and parasitoids. To prolong the efficacy of transgenic cotton against Helicoverpa species, a resistance management plan (RMP) was implemented. This plan was largely based on information from studies of the ecology and population genetics of H. armigera, and the outputs of computer simulation models that used biological information to predict the likelihood of resistance under different scenarios.