The Dutch School Inspectorate defines achievement-oriented work (AOW) as the maximization of student performance in a systematic and goal-oriented way. Research by the Inspectorate shows that students in achievement-oriented schools perform better than students in schools that meet the criteria for achievement-oriented work less. The University of Twente has developed a training course in which school teams learn to work in an achievement-oriented way. Parallel to the training activities, the effects of training schools are studied. The research findings show that the training course has a positive effect on attitudes towards AOW, as well as on knowledge and skills relevant for AOW of school staff.