As an environmental treaty under the umbrella of the United Nations Environment Programme, CMS provides a global platform for the conservation and sustainable use of migratory animals and their habitats. CMS brings together the states through which migratory animals pass, range states, and establishes the legal basis for internationally coordinated conservation measures throughout a migration area.

Migratory species threatened with extinction are listed in Appendix I of the Convention. CMS Parties work to strictly protect these animals, to conserve or restore the places where they live, to mitigate obstacles to migration, and to control other factors that could put them at risk. In addition to establishing obligations for each state adhering to the Convention, CMS encourages concerted action among range states for many of these species.