This report was prepared for the Office of Fair Trading to inform its market study into the use and re-use of information collected, stored and disseminated by public bodies. Using data collected by the OFT during the course of the market study, this report quantifies the current economic value of public sector information to the UK (we have estimated this to be approximately £590m) and the likely scale of detriment given the operations and behaviour of public sector information holders, for example in distorting access to information which they hold or in setting high charges (we have estimated such forms of detriment to be of the order of £500m). This report can be downloaded here or as Annex G from the OFT’s main report, found on its website.