The growing attention to transparency is not an accidental and fashionable wave, soon to be replaced by another timely topic in environmental governance. Transparency is here to stay and to further develop in environmental politics, as it piggy-backs on a number of wider social developments. In assessing the achievements of transparency to date, this article concludes that it has on balance been positive for democracy. But this overall positive past assessment does not automatically extend into the future, as new challenges (and thus new research agendas) lie ahead. The growing importance attached to transparency in environmental politics ensures that it becomes a central object of power struggles, with uncertain outcomes in terms of democracy as well as environmental effects. Markets and states seek to capture transparency arrangements for their own goals, which may not necessarily be in line with assumed normative linkages between transparency, democracy and participation.