Traumatic experiences can evoke serious problems, mostly described through the concept “post-traumatic stress disorder”. This syndrome, however, often does not suffice to gather all diverse problems resulting from having experienced a trauma, certainly when considering the consequences of “complex trauma”. Therefore, studies with adults have led to a new conceptualisation of the complex of symptoms characterizing the consequences of complex trauma as “Complex PTSD”. This new concept, however, is not very useful for the population of minor victims of complex trauma. This is the reason why van der Kolk and colleagues (2005) as possible alternative proposed the concept “Developmental Trauma Disorder”, indicating the problems children can develop after complex trauma. This research aims at investigating whether this new concept is suitable for use in populations of children victims of complex extra-familial trauma (e.g., war, violence, flight experiences, torture,…), as research up till now is limited to complex intra-familial trauma. Therefore, three successive research lines will be executed in this project.