© 2016 Informa UK Limited, trading as Taylor & Francis Group. Practitioners are being placed under increasing pressure to evaluate the success of their outreach activities, both by government and by their own universities. Based in a reductionist doctrine of ‘evidence-based practice’, there is a desire to demonstrate the effectiveness and value-for-money across activities that now account for around £175 million per year across England. This article examines some of the difficulties in evaluating the complex social world of outreach and suggests a ‘small steps’ approach to overcome some of these. This uses the idea of a transformative ‘theory of change’ as a framework for understanding the particular contribution made by discrete activities within a wider portfolio, providing a more reliable form of inference than attempts to ‘prove’ impact over longer timeframes.