- There has been no reported research comparing Jewish Israeli and Palestinian adolescents regarding the effect of ongoing political violence on adolescent psychosocial, family, post-traumatic stress disorder (PTSD) and aggression problems. To compare Israeli and Palestinian responses regarding the relationship between exposure to traumatic events and psychosocial, behavioural, emotional and family problems. A cluster sample of youths aged 14-18 years, including 442 Jewish Israeli adolescents in Ariel, Haifa and Tel-Aviv, and 450 Palestinian adolescents in Gaza cities, villages and refugee camps were surveyed in 2006 using our Traumatic Events Questionnaire (TEV), the Brief Symptoms Inventory (BSI), the PTSD Symptom Scale - Interview (PSS-I), the Index of Peer Relations scale (IPR), Buss-Perry Aggression Questionnaire (BPAQ) and the MacMaster Family Assessment Device (FAD). Palestinian respondents had higher scores in the TEV, BSI, PSS-I and BPAQ questionnaires, and greater problems in functioning as revealed in the IPR and FAD. The social functioning of the adolescents with their peers predicted mental health symptoms and PTSD symptoms. Lower socioeconomic status predicted mental health symptoms, PTSD, pathology of participants' family functioning and the social functioning of the adolescents with their peers. Parents' education positively effected the FAD score and the avoidance item on the PSS-I, and religiosity improved the score on the FAD. Females reported more symptoms on the BSI and PSS-I than males, and males more symptoms on the FAD and IPR than females. Both respondent groups had significant emotional and behavioural problems. Individual and community treatment, and community and social development, are likely to be useful for both populations, particularly Palestinians.