This article describes a research study on aggressive behaviour among students in middle school. The study was initiated in response to concern about agressive behaviour held by the school administration. A survey on aggressive behaviour was administered and followed by interviews with a sample of students. Student interviews highlighted a number of very important issues to consider when assessing and responding to aggressive behaviour in a school: school crowding , the playing out of dominant masculinity, involving students in finding solutions to identified problems, and considering the role of the whole school culture in sustaining agressive behaviour.