Peppimenarti (pop. 150-200) and Palumpa (pop. 100-150) are aboriginal communities 200-250 km South-west of Darwin (Map 1). No mosquito collections or surveys have been made previously in these areas, although the Department of Health Medical Entomology Branch has conducted surveys at nearby Wadeye. This survey was conducted to establish more precisely the health risk presented by mosquitoes to the communities at Peppimenarti and Palumpa - in terms of species present, their abundance, breeding areas, and the viruses they carry.