Previous research has found differences between adults' and students' perceptions of adolescents' aggressive behaviour. This study examines teachers' perceptions of physical aggression among New Zealand secondary school students. A survey assessed teachers' perceptions of problematic behaviour, and physical aggression by students towards teachers. An online survey assessed students' self-reports of physical fighting and weapon carrying. The findings show that, while teachers did not consider physical aggression a major problem in their schools, they did report frequent occurrences of physical fighting. Some teachers also reported experiencing significant physical aggression towards them by students. Student aggression was not significantly associated with teachers' perceptions of physical aggression in their schools. Teachers are facing physical aggression in their workplace, making schools a stressful working and learning environment. (Contains 6 tables and 3 figures.)