Background: Little is known about the total population prevalence and socie
tal costs of posttraumatic stress disorder (PTSD); this report reviews rele
vant literature on these topics. Method: A literature search of computerize
d databases for published reports on trauma and PTSD was conducted. This li
terature was reviewed to find data an general population exposure to trauma
, conditional risk of PTSD among those exposed to trauma both in focused sa
mples of trauma Victims and in general population samples, and the adverse
consequences of PTSD. Results: PTSD was found to be a commonly occurring di
sorder that often has a duration of many years and is frequently associated
with exposure to multiple traumas. The impairment associated with PTSD in
U.S. samples, where the majority of research on these consequences has been
carried out, is comparable to, or greater than, that of other seriously im
pairing mental disorders. Risk of suicide attempts is particularly high amo
ng people with PTSD. Available evidence suggests that the prevalence of PTS
D and the adverse emotional and psychological consequences of PTSD are much
greater in the many countries around the world that are in the midst of ar
med conflicts involving political, racial, or ethnic violence. Conclusion:
PTSD is a highly prevalent anti impairing condition. Only a minority of peo
ple with PTSD obtain treatment. Early and aggressive outreach to treat peop
le with PTSD could help reduce the enormous societal costs of this disorder
.