During the 16-year civil war in Mozambique thousands of children were separated from their families as a direct or indirect result of conflict and displacement. International organizations lent support to a national family tracing and reunification programme coordinated by the government Department for Social Action. Drawing on the findings of an empirical study of the sustainability of substitute family care, this article describes the tensions associated with the involvement of international organizations during the emergency conditions of the war, in post-war (...) rehabilitation and in longer term development. It explores the ethical dimensions of social welfare interventions across borders and continents and concludes by arguing a case for international humanitarian agencies to base their interventions to ?help? separated children on deeper knowledges of the social and political history, and the values, beliefs and normative practices of the populations with whom they work. (shrink)