We developed procedures to foster orphaned African green monkey infants to females with natural infants of a similar age to the foster infant (< 1 month). Our purpose was to assess the feasibility of fostering additional infants to females with natural infants. The subjects were 4 infants (age 1 to 5 days) that were removed from the natural mother because of neglect or trauma. The recipient females varied in parity (0 to 7 previous infants). Within 24 h of removal from the natural mother, the foster infants were presented to a group of potential recipient females by placing the foster infant directly into the cage of the female that demonstrated positive behavior toward the foster infant (reaching toward the infant and lip-smacking). Analysis of the behavioral data collected when the infants were 3 to 6 months of age indicated that foster mothers spent significantly more time nursing the natural infant alone, but the percentage time spent nursing both infants simultaneously was not significantly different than the time spent nursing either infant individually. No significant differences between weaning weight of the natural and foster infants or single infants were observed at 6 months of age. Overall our success rate at weaning (75%) suggests that fostering additional infants on females with a natural infant may be a viable strategy for raising orphaned African green monkeys and may prevent the development of abnormal behaviors that typically are manifested by nursery-reared infants.