Pocket monkeys, otherwise known as pygmy marmosets can be purchased from authorized exotic animal sellers online such as Exotic Animals for Sale, Primate Store and Poggi's Animal House. These are directory listings that feature breeders and pet owners that have these monkeys up for sale. In most cases, pickup has to be done in person, even though the actual purchasing can be completed online.

The pygmy marmoset is the smallest breed of primate in the world, and it is found exclusively in the jungles of South America. On average they are around 7 to 10 inches long from head to tail. Owning a pygmy marmoset is a large responsibility. When they are still babies, they need to be bottle fed. They also need to live in groups for the first portion of their lives, so they can learn to socialize. It's important to note that ownership of monkeys is outlawed in several states. Before buying a pygmy marmoset, it's advised that the prospective pet owners check their state regulations to see whether they can own a monkey or not. Some states require buyers to possess permits from the United States Department of Agriculture in order to be permitted to legally own monkeys.