In this dissertation, I study the production and evaluation of information regarding the sustainability performance of firms. Specifically, I study voluntary sustainability reporting and environmental ratings of firms as mechanisms of private environmental governance systems. In my first study, I ask how the institutional environment impacts how these mechanisms interact with and facilitate other governance structures. I find that differences in sustainability reporting across S&P 500 firms from 2007-2015 are driven significantly by firm sustainability strategy, industry materiality of environmental disclosure, and legitimacy pressures resulting from the institutional environment. In my second study, I focus on the impact of changes in mandatory and voluntary sustainability reporting on agreement among environmental, social, and governance (ESG) ratings with regard to environmental ratings and scores. I find evidence that firm-specific agreement in environmental ratings and scores increased over the period 2007-2015 using a sample of US public firms. Further, I find that firm-specific average environmental score disagreement decreased more significantly for firms in industries newly impacted by mandatory emissions disclosure requirements. Overall, these findings illustrate how variation in voluntary disclosure through sustainability reporting reflects both sustainability strategy and the stakeholder orientation of the environment in which firms operate. Further, they show how mandatory disclosure changes are reflected in private environmental governance systems, as organizational fields and field governance mechanisms adapt to and incorporate these changes.