Squirrel monkeys provide ecological, commercial, and research values. Ecologically, they are integral to tropical food chains in Central America and South America, where they feed on insects, fruit, and other food sources (small vertebrates, nectar, leaves, etc.), while themselves being prey for snakes, cats, and raptors. For humans, the common squirrel monkey (S. sciureus) is captured for the pet trade and for medical research (Rhines 2000). While it is not endangered, three squirrel monkey species are in danger of extinction. S. o. oerstedti is listed as "endangered," S. o. citrinellus is listed as "critically endangered," and S. vanzolinii is listed as "Vulnerable."
In addition to these values, squirrel monkeys add to the enjoyment of nature for human beings, whether see in the wild moving from tree to tree or observed in zoos.