To maintain a self-sustaining European Endangered Species Programme (EEP) population of Gorillas Gorilla gorilla gorilla, it is necessary that as many individuals as possible contribute their genes to the population. It is believed that hand-rearing may prevent the development of a good repertoire of natural social behaviours that would facilitate successful breeding when individuals reach sexual maturity. Between 1980 and 2004, 464 Gorilla births resulted in 117 individuals [63.54 (♂.♀)] being hand-reared. In this review, we analyse information gathered from a questionnaire survey, augmented with data from the international studbook and other publications, to identify the conditions that contribute to breeding success. Hand-reared ♀♀ should initially be introduced into socially competent groups that breed (so they can observe breeding by conspecifics) and, in addition, be introduced to an experienced breeding ♂. Similarly, hand-reared ♂♂ should initially be placed in socially competent groups and, in addition, should be introduced to mother-reared adult ♀♀ that, where possible, have also had previous breeding experience. Although the receptor group and the personality of hand-reared individuals need to be considered before making decisions about introduction to conspecifics, in order to increase the genetic contribution that hand-reared Gorillas make to the EEP population, factors recorded in this article may provide guidance on how to improve captive breeding for the conservation of this species.