Funded by the Government of Western Australia and run by the Geological Survey of Western Australia, WA-ARRAY is designed to investigate the crustal and lithospheric mantle structures with the primary aim of identifying prospective regions for mineral exploration, especially in areas undercover. Considering WA’s rich Precambrian tectonic history, WA-ARRAY will also provide an unprecedented opportunity to study lithospheric structure related to early Earth tectonics and evolution. WA-Array will deploy a series of temporary arrays of 165 seismometers in a grid pattern at 40-km station spacing. In a 10-year period, WA-ARRAY will cover the entire state (over 2.5 million square kilometers) with 1600 sites and is expected to become one of the largest passive seismic programs undertaken in the world.