Purpose – The purpose of this paper is to examine the reporting practice of leading museums in New Zealand (NZ) and the UK to develop a museums' performance accountability disclosure index. Design/methodology/approach – The paper reports a study of annual reporting by 16 museums in NZ and the UK. Because of the unique nature of the industry the disclosure index uses a framework which draws on the balanced scorecard (BSC). The BSC provides a link between internal reporting of key performance issues and the need of a community organisation to report to the public. Findings – Overall, the quality of reporting in each country is found to be of a similar standard. The strongest parts of reports are those dealing with internal processes and objectives, and the weakest are those reporting on learning and growth. Originality/value – Museums are a key repository of tangible cultural heritage of huge intrinsic value both to the community now, but of more importance to future generations. However, the performance and accountability of this sector is basically without research or commentary, and this paper addresses this deficiency.