This article explores teachers' perceptions of the effects of high student turnover in international schools in the UK. The research used a "grounded theory" approach for qualitative data collection and analysis, based on interviews with eight teachers in four international primary schools. The results of the grounded theory suggest that a process of "systemic containment" develops which helps the whole class, including newcomer pupils and their teachers, to cope with the frequent transitions. The discussion emphasises the role of the educational psychologist in encouraging teachers to become more informed and reflexive about inclusion of newcomers from abroad. (Contains 1 note.)