If you see someone with a pet monkey it isn't difficult to get that immediate thought of "How cute!" or "I want a pet monkey!" but the reality of having a primate as a pet is far from the public's instant perception.
Kinds of Monkeys Kept as Pets
Capuchin - This little primate is often seen in movies and television and is famous for it's small size and mischevious nature. They are highly intelligent, territorial, and will live up to years in captivity. That's 40 years of diapers in case you didn't realize they don't learn to use the toilet.
Chimpanzees - This is the largest kind of primate typically found as a pet and isn't actually a monkey (they are apes). Chimps are also often seen in movies and on television. Many reports of chimps attacking their owners and other people, even killing them, have continued over the years. Chimpanzees are large, strong, males especially are very aggressive, and they can live over 60 years. These are not household pets.
Macaques - These smaller primates can live up to 30 years, need diaper changes, large, secure cages so they don't get lost in your house or run around outside and climb up electric poles (which is often the outcome). Even though these are smaller primates they still require extremely large enclosures, at least 30 feet squared. Many zoos don't even provide primates with the appropriate amount of space.
Tamarins - These are tiny primates that weigh less than a pound but will live about 15 years in captivity. They can still deliver a nasty bite despite their small mouths and need very secure cages with tiny bar spacing or they will escape or get stuck in the bars.
Squirrels - These are very acrobatic monkeys. They will live up to 25 years, use their tail to hang on branches, and need a lot of space (as does any primate). They will also wear diapers their entire life and eat a variety of foods.
Marmosets - Similar to the Tamarins in size and housing requirements, Marmosets are teeny-tiny primates. They are quick and not suited for handling since they don't exactly just sit still in your lap.
Guenons - These are about 10 pound primates that live about 25 years in captivity. Guenons, like all primates, are very high maintenance. There are almost two dozen different species of Guenons with the Green monkey, Vervet and Grivet possibly the most popular three found in captivity. They thrive in large groups, therefore one is not suited to live in a house of humans.
If you are considering getting a pet monkey just remember a few things. They are expensive, dangerous, live a long time, require a huge amount of your daily time, need a lot of space, and are not cuddly. Yes, some monkeys live out their lives without causing harm to a human and are properly cared for as pets. Many handicapped individuals even rely on primates to do daily tasks. But a pet primate that has to stay in a cage, has little to no daily enrichment or activity, is lonely, and gets an unhealthy diet is a miserable pet. It's animal abuse, actually, for someone to "care" for a pet primate like that.
Primates, some of which can be referred to as monkeys, are highly intelligent creatures. Anything that is as smart as a human child and stronger than a grown man needs extraordinary care - or to be left in the wild. Now I'm not telling you you can't have a pet monkey if you want one. But I am saying please be practical and prepared. Primates do not make good pets and the larger ones especially should not be kept in captivity (i.e., chimpanzees). If you don't believe me just ask a former chimp owner.