Another thing - this breed picks up on the energy field of others, including yours. If there is something amiss, they will react and potentially attack another person / stranger who you "say" with your energy might not be wanted or invited. That is what they are supposed to do. By the same token, if you tell them "it's ok" or whatever your training words will be to know something is acceptable, they should immediately stand down, this includes one off strangers like service people who are there once and gone. Best to leave them separated.