Transparency has become the watchword of twenty-first century liberal democracies. It refers to a project of ‘opening up’ the state by providing online access to public sector data. This article puts forward a sociological critique of the transparency agenda and the purported relationship between institutional openness and public trust. Drawing upon Simmel’s (1906) work, the article argues that open government initiatives routinely prize visibility over intelligibility and ignore the communicative basis of trust. The result is a non-reciprocal form of openness that obscures more than it reveals. In making this point, the article suggests that transparency embodies the ethos of a now-discredited mode of ‘instrumental politics’, reliant on the idea that the state constitutes a ‘domain of plain public facts’ (Ezrahi, 2004: 106). The article examines how alternative mechanisms for achieving government openness might better respond to the distinctive needs of citizens living in late modern societies.