There is growing enthusiasm for transparency in public affairs. Discourses idealising the value of transparency are part of the rhetoric of advocates of ‘good governance’. However, there is little discussion of the justifications for transparency. The view that transparency underpins legitimacy is similar to that of the advocates for ‘publicity’ in the initial era of representative government, when transparency (or publicity) became a crucial issue in political debates. This article identifies the intellectual roots of claims for transparency through a retrospective examination of the initial pleas in its favour. It concentrates on Jeremy Bentham, who provided an extended inventory of reasons for publicity. We examine Bentham’s major arguments and how they are currently analysed. We conclude that the virtuous effects of transparency are today qualified by criticisms in scholarly work which emphasise the possible costs and perverse effects of the search for transparency or demonstrate that it may fail to deliver the expected benefits.