Acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) are psychological reactions that develop in some people following the experience of traumatic events such as major disaster, war, sexual or physical assault, motor vehicle accidents, and torture. Exposure to a traumatic event is not an uncommon experience. Large community surveys in Australia and overseas reveal that 50–65 per cent of people report at least one traumatic event in their lives. The volume of research studies on the treatment of ASD and PTSD published over the past decade, and the emerging consensus from those studies, warrants the development of clinical practice guidelines. The guidelines were developed in accord with National Health and Medical Research Council guideline development requirements, by a working party comprising key trauma experts from throughout Australia, in consultation with a multidisciplinary panel comprising representatives of the range of health professionals involved in the care of people with ASD and PTSD, and service users.