Transparency is increasingly evoked within public and private climate governance arrangements as a key means to enhance accountability and improve environmental outcomes. We review assumed links between transparency, accountability and environmental sustainability here, by identifying four rationales underpinning uptake of transparency in governance. We label these democratization, technocratization, marketization and privatization, and assess how they shape the scope and practices of climate disclosure, and to what effect. We find that all four are discernible in climate governance, yet the technocratic and privatization rationales tend to overtake the originally intended (more inclusive, and more public-good oriented) democratization and marketization rationales for transparency, particularly during institutionalization of disclosure systems. This reduces transparency's potential to enhance accountability or trigger more environmentally sustainable outcomes.