While the purpose, effectiveness and legitimacy of parliaments has been a topic of discussion among political philosophers and politicians for centuries, the measurement of the institutional performance of parliaments is relatively undeveloped compared with that of the executive public sector. This paper reveals a desire amongst parliamentary officials and some politicians to measure the institutional performance of parliaments, but it also questions the potential effectiveness of many of the more obvious measures that could be deployed. The difficulties uncovered relate particularly to the challenges of disaggregating public perceptions of parliament from those of government, and to the limited applicability of some principles of performance measurement to the parliamentary context. The analysis on this paper suggests that the most promising way to build on the desire for change is to develop measures of the impact of parliamentary outreach work in parallel with raising the effectiveness of parliamentary administration through improved performance measurement and management.