The scope and scale of information provision as environmental policy has grown dramatically in recent decades. In principle, disclosure instruments hold great promise. In practice, the evidence is mixed. This chapter reviews what we know about environmental information provision from a policy perspective. The survey considers theories and mechanisms potentially driving outcomes, potential advantages of disclosure programs relative to alternatives, the empirical evidence on effectiveness, implications for policy and practice, and gaps in knowledge. Environmental information provision, despite potential theoretical and political promise, is not a proverbial magic bullet. Environmental disclosure in the real world is complicated by subtle design details and behavioral realities.