Results suggest that standardized diagnostic screening instruments can be adapted to local cultures in resource-poor countries and be reliably applied by trained local psychosocial workers or teachers. All teachers in this study reported having repeatedly experienced traumatic stress. With the revelation that a high number of children experience traumatizing events, it is not surprising that about 1 in 4 children suffers from PTSD. The results provide an exact and quantitative answer to the question of how well teachers are able to perform screening for post-traumatic stress disorder (PTSD) and co-morbid symptoms after a short and focused training session; in five of the six schools included in the survey, teachers achieved valid results. In a sixth school, the 100 percent PTSD-prevalence outcome was not valid. Post-hoc inquiry did not indicate that the corresponding teachers were not able to understand the application of the instrument; rather it seemed that political motivation had produced a significant bias. Adverse consequences of the traumatic experiences on mental health and normal development were disclosed. Data were collected as a randomized, epidemiological screening of children attending school; fifth grade children from 16 different primary schools were randomly chosen from all 5 administrative zones of the North Eastern Tamil Provinces of Sri Lanka for participation is this survey. Table, figures, and references