At least two U.S. statutes and one international treaty protect endangered and threatened species:

The Endangered Species Act of 1973 forbids any killing of endangered species in the United States and the import of endangered animals. The Fish and Wildlife Service lists which species are endangered, based on its own research and petitions from interested groups or foreign countries. Animals may be designated as endangered or threatened depending on their status. Some threatened species may be imported on a limited basis, but only if Fish and Wildlife publishes a special rule permitting it.

The Convention on International Trade in Endangered Species (CITES) is designed to protect wildlife from detrimental trade. Its 109 signatory countries meet every two years and vote on the listings of animals to be covered. The treaty became effective in 1975. Animals and plants are listed in three appendices; Appendix I is the strictest level of protection and allows no commercial trade. Limited sport hunting may be permitted but only if the hunter acquires special export and import permits from the countries involved. In the United States, CITES violations are illegal under the Endangered Species Act.

The Lacey Act forbids import or trafficking in wildlife taken in violation of any U.S. or foreign wildlife law.

Only a fraction of the world's species are listed under CITES or the Endangered Species Act. Hundreds of species have been proposed for listing, and many have yet to be reviewed. "Beyond that you've got a whole host of species whose status is unknown," according to Michael Sutton of the World Wildlife Fund. "There's just been no research done on the population status. In many cases, these animals are unprotected."