Much of the research into behaviour problems and school interventions has focused on primary school-age children. In the primary school setting, the behaviours that cause the most concern to teachers are frequently occurring but relatively minor behaviours such as calling out and interrupting the learning of others. These minor problematic behaviours have been shown to respond to low-level interventions that are presented as written advice. The behaviours that secondary school teachers perceive as problematic, and the preferred method of intervention, have received comparatively little attention in the research. An investigation of the behaviour problems that high school teachers find most troublesome was conducted in this study. It was found that similar behaviours were reported as troublesome in the secondary school classroom compared with the primary classroom, although differences were demonstrated across year levels. Teachers were also surveyed about their preferred method of intervention/assistance for these behaviour problems. This information about intervention approaches informs the development of strategies for assisting classroom teachers.