In response to demand from investors and other stakeholders, companies have increased voluntary disclosure of climate change-related policies and performance. Information intermediaries have correspondingly emerged to provide needed credibility and commensurability of climate disclosures. However, the provision of performance ratings and lax audit capabilities creates opportunities for firms to manipulate those ratings for impression management. This article explains how firms may attain an intermediary's favorable assessment of climate performance using varied methods of strategic disclosure. Using data from a prominent climate intermediary (CDP, formerly the Carbon Disclosure Project), I find that strategic disclosure is widespread and effective in attaining higher ratings, particularly through disclosure of forward-looking factors, suggesting that ratings may not be an accurate indicator of a firm's true underlying performance. This article contributes to commensuration and impression management literatures, offers guidance for mechanism design to improve the reliability of intermediated voluntary disclosure, and highlights important areas for future research. [ABSTRACT FROM AUTHOR]