An Environmental Impact Statement (EIS), in the United States, is a document that must be filed when the federal government takes a "major Federal action significantly affecting the quality of the human environment." The law requiring this is the National Environmental Policy Act.

An EIS typically has four sections:

1. An Introduction including a statement of the Purpose and Need of the Proposed Action.
2. A description of the Affected Environment.
3. A Range of Alternatives to the proposed action. Alternatives are considered the "heart" of the EIS.
4. An analysis of the environmental impacts of each of the possible alternatives.