It is now widely recognised that, when performances are evaluated only in terms of measurable results, employees and organisations find ways to ‘game’ the system. Hospitals improve patient survival rates by taking fewer high risk patients; companies maximise short-term returns to shareholders by not investing in long-term growth strategies. And in extreme cases, a narrow focus on results produces corrupt behaviour – for example, manipulating a company’s financial results to make its performance look better than it is. There are obvious lessons in this experience for current efforts to improve educational outcomes. Following the model adopted in business, education systems in a number of countries are now attempting to drive improved performance by placing a strong focus on results such as student test scores, participation levels and school completion rates. These results metrics are being used to set targets for improvement and to hold teachers and schools accountable for producing better results, often with accompanying incentive schemes. However, there is growing evidence that focusing on results alone is an ineffective improvement strategy in many contexts and often leads to unintended and undesirable behaviours. Exhortations and incentives to improve are of limited value if equal attention is not paid to the guidance and support employees need to make improvements in their practice.