Participants in this study were 791 children (402 girls, 389 boys) from 10 schools within 1 school district in Sarajevo, Bosnia. This is one of the few studies to examine children's posttraumatic stress reactions and adjustment while in the midst of war. Another unique aspect of this study was the examination of children's reactions to cumulative trauma, as well as to two conceptually different types of trauma: violent and nonviolent. Findings reflect a pattern of differential exposure by age. Older children were more likely than younger children to be exposed to violence and to have relatives and friends who were killed during the war. Older children were not more likely to self-report trauma symptoms, perhaps reflecting a pattern of symptom denial for older children or a pattern of high distress among younger children even at lower levels of trauma exposure. Sex differences were largely nonsignificant. Tables, references