ASTSS has now existed in Australia and New Zealand for over 23 years. Interest in forming an Australasian Society was initiated in the late 1990s by several people, including Ruth Wraith and Dr Sandy McFarlane, following their involvement in the International Society for Traumatic Stress Studies. A steering committee, with representatives from Queensland, NSW, Victoria, South Australia and Tasmania, was convened, and met in Sydney in 1991 to formulate the establishment of the society. This had built on activities already taking place in several states and territories. ASTSS was then formally constituted in 1993, by which time chapters had been established in several states. The first, very successful, national conference was held in Adelaide in April1993, and this was followed every year with a national conference or a speaker tour. The initial structure of ASTSS was built around a central committee and chapters, with the latter being eventually established in all Australian states and territories and New Zealand.

One landmark achievement for ASTSS was the organisation and hosting of the 2000 World Congress in Melbourne on behalf of ISTSS, which was attended by over 1000 delegates, and literally placed ASTSS on the world trauma studies map. The Congress also placed ASTSS in a strong financial position and enabled to pursue its goals. These goals and strategies to achieve them were articulated in a detailed Strategic Plan in 2001. This Strategic Plan formed the basis for a number of initiatives such as the Media Award, the Research Awards, the quarterly Newsletter, establishment of a website, and the organisation of conferences and workshops. ASTSS has outlived a number of other trauma societies that emerged in the 1990s, and formed over time, highly productive partnerships, particularly with ACPMH, now Phoenix. The society has endured, but evolved over time, but it remains committed to its primary goal: To provide an academic and professional forum for the advancement of knowledge about highly stressful experience and the etiology, prevention and treatment of the unwanted consequences of traumatic experience.