Since the onset of the dog’s domestication more than 400 breeds have arisen. Owing to a long process of breeding implying the exposure to a variety of selective pressures, these breeds show notable behavioural differences. The aim of this study was to compare different breeds of dogs with regard to their behavioural responses in the BPH, a behaviour and personality test for dogs, and to validate the BPH. 856 dogs of 27 breeds were compared on the basis of their official BPH results. Further, video recordings of three specific test aspects were used for a detailed behavioural coding of 64 dogs of 9 breeds. The results suggest large behavioural differences between dog breeds concerning their responses in the BPH. In contrast to the officially recognized breed grouping according to the breeds’ historical function, cluster analysis revealed only two main clusters of breeds. This suggests that breed-typical behaviour may have changed over time in response to the shift in selection pressure which resulted from changing intentions of breeders. Moreover, it underlies the importance of current selection criteria for the behavioural shaping of dog breeds. The results obtained by the direct ethological recordings suggest that differences in the dogs’ personality are expressed mainly in differences in body posture and vocalisation. Strong correlations between the results of the ethological recordings and the official BPH results which are based on rating scales suggest that the BPH is a valuable tool for describing behavioural traits in dogs.