This paper examines organisational change processes that occur when accountability demands from powerful external stakeholders change. It investigates, firstly, whether these external accountability demands impact on the performance management systems of two different types of organisations. Secondly, it considers whether the goals for improved performance contained within the external accountability demands are realised. The paper derives its primary insights from analysing in-depth interviews with managers working in a private sector company and in public sector organisations. The analyses reveal complex organisational responses. In the public sector case study, the organisations tended to reorient their performance management systems towards the external accountability demands; whilst in the private sector organisation, pressures from falling share prices forced managers to focus their decision making on the preferred performance measures contained in shareholders’ accountability demands. However, whilst there is some evidence of performance management system changes, the desires for improved performance subsumed by the external accountability demands are not necessarily realised through the performance management system changes.