A U.S. National Marine Sanctuary is a federally designated area within United States waters that protects areas of the marine environment with special conservation, recreational, ecological, historical, cultural, archeological, scientific, educational, or aesthetic qualities.

The program began after the 1969 Santa Barbara oil spill off the coast of California brought the plight of marine ecosystems to national attention.

The resources protected by U.S. national marine sanctuaries range from coral reef ecosystems in American Samoa, Florida, Hawaii, and Texas, to shipwrecks in the Great Lakes and the Atlantic Ocean.

The NMSP jointly administers the Papahānaumokuākea Marine National Monument in conjunction with the United States Fish and Wildlife Service and the State of Hawaii, and it jointly administers the Rose Atoll Marine National Monument with the U.S.

[7] The private nonprofit organization Marine Conservation Institute has compiled fact sheets for each sanctuary listing activities which are directly regulated by the NMSP.

NOAA prepares a Final Environmental Impact Statement (FEIS) that addresses the concerns raised in the DEIS process and distributes it for comment.