We don't feel that primates make good pets, it is very difficult to provide them with the appropriate conditions to keep them in good health and cater for their welfare needs. Below we provide a link to a DEFRA consultation on the keeping of primates as captive species.
Many people however do keep them in excellent zoo-type housing, or even better than some zoos. These are not being kept as pets, there is no companionship aspect. In this regard these keepers may be doing an very important job in maintaining a genetic base for a species which is losing habitat in the wild.