Summary The purpose of this study was to examine the effectiveness of a whole school behaviour management programme on teachers? use of encouragement in the classroom. Given that the performance of the school has become an important dependent variable in school effects research, it follows that interventions which address behaviour management and the improvement of academic performance, have also taken on a school?wide focus or orientation. In Australia, where this study was conducted, there has been an increased interest in the (...) use of school?wide behaviour management and discipline programmes, which are characterized by their focus on improving teachers? classroom management skills. In the present study randomly selected teachers from schools involved in a school?wide behaviour management programme participated in an experimental evaluation of the effects of the programme. Continuous data collection indicated that the majority of teachers made increases in their use of encouragement over the course of the intervention. However, observations conducted during a follow?up phase revealed reductions in levels of encouragement following the withdrawal of the intervention. (shrink)