Basic ethical principles like autonomy, non-maleficence, beneficence and justice should be taken into consideration step by step when treating refugee children and their families. These principles may be considered from the point of view of each of the actors involved--patient, therapist and interpreter. This paper is focused on the role of the interpreter and on different aspects to be considered by the therapist when working with interpreters in psychotherapeutic treatment of refugee children and families. Elements of case histories are used to illustrate situations faced in working with an interpreter. An ethical analysis of a case where a teenage refugee received therapeutic treatment using an interpreter is made.