This report provides a critical overview of impact evaluation in the museums, archives and libraries sector. The study, funded by Resource: The Council for Museums, Archives and Libraries, consisted largely of a review of the literature published during a five year retrospective period, with a particular emphasis on impact evaluations conducted within the UK. An advisory group, representing all three domains, was also established. The methodologies used in, and the evidence obtained from, these evaluation studies are discussed critically within the broad context of social, learning and economic impact. While there is an abundance of anecdotal evidence and descriptions of best practice in the sector, extensive hard evidence of impact, gathered systematically, is often lacking. The most compelling evidence from the review indicates that the sector has an impact on personal development. There is also a current emphasis on the impact evaluation of special projects and initiatives; a shift in emphasis towards the evaluation of core services will require a corresponding shift in professional thinking. Issues relating to physical, emotional and intellectual access to the sector by individuals or groups deemed to be in danger of exclusion are also discussed. While the profession is beginning to recognise access as a priority, there is a need to increase access throughout the sector in order to enable impact. The report concludes with a series of detailed recommendations for follow-on work, including: further consultation on impact evaluation, both within and outwith the sector; further research into economic impact, long-term impact, the impact of the archives domain, and the establishment of causal relationships between sector use and social, learning and economic impact; further development of, and access to, appropriate evaluation techniques and tools; increased support for evidence-based practice; and the development and adoption of a strategic plan for the sector.Resource: the Council for Museums, Archives and Libraries