Rhys is quite the little watch dog. He barks at strange sounds outside and, if he sees anyone outside the apartment, he lets out his "big" bark. I was on the phone with a credit card rep the other day and Rhys decided to bark. The guy said, "That's a big dog, huh?" and I said, "Actually, he just THINKS he's big."
But once inside, all strangers become friends. But I don't know what he would do if someone came in who was NOT let in by me.