Editors' Summary: EPA has set numerous records in recent years in assessing civil penalties against violators of environmental laws. This Comment explains how EPA uses guidance documents called civil penalty policies to calculate civil penalties. The various federal environmental statutes leave EPA with considerable discretion in setting a civil penalty amount. The author describes this statutory framework and then discusses the role of EPA's civil penalty policies in administrative and judicial enforcement actions. The Comment outlines EPA's general policy on civil penalty assessment and then turns to EPA's numerous statute-specific penalty policies. The section on statute-specific policies includes a table listing key facts for each provision of a statute that authorizes EPA to seek civil penalties. Finally, the Comment addresses the criticism of EPA's implementation of the policies and EPA's response to the criticism.