Fall armyworm (FAW, Spodoptera frugiperda) is a significant global biosecurity threat because of its ability to spread rapidly within and between countries. It is a typical transboundary pest species that cannot easily be contained by individual country quarantine restrictions. In Australia, as elsewhere, the characterisation of FAW, including clarification of insecticide resistance status is an important first step in informing the development of management strategies and identification of R,D&E needs. This project will utilise two separate approaches involving bioassays of selected insecticides and Bt Toxins, and whole genome sequencing methods to characterise resistance genes, thereby providing a holistic understanding of resistance threats posed by the FAW to Australia's and South East Asia's agricultural sectors.