Research voyages aboard the Australian Marine National Facility vessel RV Investigator in June 2022 and its predecessor RV Southern Surveyor in 2006, 2008, and 2013 have investigated the numerous submarine landslide scars present on the South-Eastern Australian Continental Margin offshore New South Wales and South-Eastern Queensland. The preliminary interpretation of the entire body of data provides two key findings which will be of interest to Australia’s state and federal natural hazards management authorities. Firstly, the larger and probably tsunamigenic mid-slope submarine landslides are developed on segments of the continental slope where the geological basement blocks have subsided to deeper levels than is the case on adjacent areas of continental slope where large failures are generally absent. Secondly, while it is probable that the large submarine landslide events occurred sometime after the late-Pliocene (approximately 3 million years ago), there is surprisingly little evidence for volumes of landslide debris equivalent to the volume of material removed from the landslide scars present on the lower continental slope or abyssal plain downslope of the landslide scars. This indicates that there has been sufficient time for much of the landslide debris material to have been removed by currents and other processes. There is also good morphologic evidence for recent strong bottom currents and pronounced erosion at the base of the east Australian continental margin in the northern Tasman Sea. These observations suggest that there has been a geologically short, but significant time-gap between an episode of large mid-slope submarine landslide occurrence and the present-day. Further work is required to confirm these two findings, but if they are reliable, then the risk arising from large submarine landslides is likely less than earlier work indicates.