Livestock guardian dogs (LGDs) in the Romanian Carpathians are as old as the pastoral presence and activity in the region. The main role of these dogs is to protect livestock from predation by large carnivores. The Carpathian Mountains, as opposed to other European mountain ranges, have always had considerable populations of wolf, brown bear, and lynx; conflict with the herders is inevitable. Here, the shepherds rely only on themselves and their dogs to keep their animals safe from predation during pastoral movements. We investigated 12 sites from the historical regions of Banat and Transylvania, where we have collected traditional ecological knowledge (TEK) on the use of native LGDs as an ancient non-lethal method for the prevention of livestock depredation. By monitoring the behavior of their dogs, the shepherds establish a complex ethno-ethological relationship with them, which helps them foretell the movements and presence of large carnivores in their vicinity. We have also investigated the recent positive change of attitude of some of the Romanian nature conservationists towards the Romanian Carpathian Shepherd Dog breed, which is also currently promoted by important international nature conservation NGOs as an ecologically friendly method to mitigate the conflict with large carnivores. The uninterrupted use of endemic LGD breeds by pastoralists in Romania might be one of the main reasons for the survival and conservation of large carnivores here in the past and in the future.