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Genetically engineered crops that produce insecticidal toxins from Bacillus thuringiensis (Bt) are grown widely for pest control. However, insect adaptation can reduce the toxins' efficacy. The predominant strategy for delaying pest resistance to Bt crops requires refuges of non-Bt host plants to provide susceptible insects to mate with resistant insects. Variable farmer compliance is one of the limitations of this approach. Here we report the benefits of an alternative strategy where sterile insects are released to mate with resistant insects and refuges are scarce or absent. Computer simulations show that this approach works in principle against pests with recessive or dominant inheritance of resistance. During a largescale, four-year field deployment of this strategy in Arizona, resistance of pink bollworm (Pectinophora gossypiella) to Bt cotton did not increase. A multitactic eradication program that included the release of sterile moths reduced pink bollworm abundance by >99%, while eliminating insecticide sprays against this key invasive pest. The full paper was published online in: Nature Biotechnology (7 November 2010) doi:10.1038/nbt.1704 For more information and discussion of the article, please visit Nature Online, doi:10.1038/news.2010.585 (7 November 2010). Prolonged colonisation, irradiation, and transportation do not impede mating vigour and competitiveness of male Anopheles arabiensis mosquitoes under semi-field conditions in Northern Sudan M.M. Hassan, W.M. El-Motasim, R.T.Ahmed, and B.B.El-Sayed Department of Vector Biology and Biomedical Studies/Epidemiology, Tropical Medicine Research Institute, Khartoum, Sudan USDA-ARS, 2Medical Entomology Department, National Health Laboratories, Federal Ministry of Health, Khartoum, Sudan