Conservation biologists have long faced the challenging task of large-carnivore conservation. The hunting habits and specific ecology of these species make their conservation difficult and Wolverines Gulo gulo are no exception. Wolverines are close to extinction as a result of human persecution and habitat loss. The European Association of Zoos and Aquaria (EAZA) introduced the European Endangered Species Programme (EEP) for the Wolverine in 1994 but only irregular breeding has been achieved. The aim of this study was to identify factors that could be connected to breeding success in Wolverines in human care with a particular focus on the characteristics of enclosures, species biology, characteristics of the institutions and the influences of human-animal interactions. Based on these factors, we produced and distributed an online survey to almost all holders of Wolverines included in the EEP. Overall, no main factor or group of factors investigated in this study seemed to be the clear defining feature that would explain the differences in breeding success between institutions participating in the Wolverine EEP. However, a negative effect of small enclosures on breeding success was indicated by the results. Furthermore, zoos with non-successful breeding tended to separate keepers and Wolverines during routine enclosure maintenance compared to zoos that reported successful breeding. Both these factors are interesting and need further investigation.