Potential applications for reducing transmission of mosquito-borne diseases by releasing genetically modified mosquitoes have been proposed, and mosquitoes are being created with such an application in mind in several laboratories. The use of the sterile insect technique (SIT) provides a safe programme in which production, release and mating competitiveness questions related to mass-reared genetically modified mosquitoes could be answered. It also provides a reversible effect that would be difficult to accomplish with gene introgression approaches. Could new technologies, including recombinant DNA techniques, have improved the success of previous mosquito releases? Criteria for an acceptable transgenic sterile mosquito are described, and the characteristics of radiation-induced sterility are compared with that of current transgenic approaches. We argue that SIT using transgenic material would provide an essentially safe and efficacious foundation for other possible approaches that are more ambitious.