It has become clear through recent research in Japan and abroad that many individuals who have experienced traumatic events are suffering from post-traumatic stress disorder and other related mental health disorders. In order to deal with such conditions, several evidence-based intervention programs have been developed. On the other hand, since the 1990 s, the U. S. Department of Health and Human Services Substance Abuse and Mental Health Services Administration has been seeking ways to provide an optimal service, avoiding re-traumatization, for individuals with trauma-related disorders as well as those with physical and mental impairment and/or social problems due to Adverse Childhood Experiences. The results showed that services should not be limited to only trauma-specific intervention. It is necessary for all staff involved in such treatment to provide integrated services from the viewpoint of trauma. Under these circumstances, fully understanding the effects of traumatic events and traumatic reactions made it possible to develop the concept of trauma-informed care, which aims to improve the care system as a whole. This paper provides an outline of the historical background regarding the development of trauma-informed care and considers future expansion in Japan.
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