Natural resource damages (NRD) under federal law is a statutory cause of action to compensate for injury to natural resources resulting from releases of hazardous substances or oil. Designated officials are authorized under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and the Oil Pollution Act (OPA), among others, to act as “trustees” on behalf of the public or tribes. While many states have comparable statutes or recognize public common-law claims, the federal statutes uniquely require trustees to use damages exclusively to restore, replace, or acquire the equivalent of injured resources. NRD fills a gap at some sites where cleanup actions stop short of fully mitigating harm or compensating for the public’s loss of access. The statutory provisions and rules governing NRD claims are complex and have been interpreted in relatively few judicial decisions. This Article covers those decisions and a wide range of issues, including the scope of liability, defenses, how NRD should be measured, and the public’s role in NRD assessment and restoration planning. It also addresses how NRD claims can be resolved by settlement, including partial, “early restoration” settlements that narrow the scope before a full NRD assessment is complete.