Plants emit volatile compounds that attract insects for foraging and oviposition. We have identified the plant volatiles which are most attractive, alone and in blends, to H. armigera and H. punctigera, which are the key pests of cotton and many other summer crops in Australia. These formulations are mixed with an insecticide, methomyl, and sprayed on crops. Typically one row in every 72 is treated. In the 2002/03 season, two fields of cotton, approximately 40 ha each, were treated three times. The impact on treated and surrounding untreated fields was monitored by counting and dissecting dead moths to estimate the number of eggs which were not laid as a result of the treatment, and by regular scouting for a range of pest and beneficial insects. In the 2003/04 season, approximately 13,000 ha of cotton were treated with the formulation, under the trade name MagnetŪ with a product evaluation permit from the Australian Pesticides and Veterinary Medicines Authority. Results from both seasons indicate that attract-and-kill for female Helicoverpa spp. using plant volatiles could make a significant contribution to IPM on an area-wide basis.