The Queensland fruit fly, ‘Qfly’ is Australia’s most significant horticultural pest and is a major biosecurity problem. The adults lay their eggs in ripe fruit and the larvae feed on the flesh of the fruit, rendering it unmarketable. The sterile insect technique (SIT) is a form of biological control in which large numbers of sterile flies are used to flood the fly population, reducing the possibility of mating between wild flies and the production of fertile eggs. In this project, we aimed to develop more effective sterile insect emergence and release technologies to improve the success and cost-effectiveness of sterile Qfly releases. Guidelines for pupal release were developed including optimal pupal loadings and release timings that maximise the emergence and flight activity of sterile adult Qfly. For adult fly releases, we developed a method that maximises emergence success, flight activity, persistence, abundance and mating competitiveness of sterile male flies. Trials using chilled adult flies resulted in the development of a protocol that similarly maximises emergence, flight and longevity. A prototype device for releasing chilled adult flies from a slow moving vehicle was also developed. Overall, our results showed that significant decreases in wild fly populations can be achieved using any one of the three release methods we developed and that a method should be chosen dependent upon the location and resources available. This study also demonstrated that, based on trap recapture rates, a lower numbers of mature sterile flies (i.e. protein fed flies) need to be released to achieve control, relative to releases made using immature flies. Further studies should be completed to scientifically verify and establish the absolute number of mature sterile flies required to suppress and/or eradicate a given wild population, to minimise the requirement for sterile flies and thus further reduce costs. It is recommended that low-level sterile releases are used in towns