I guess I'm fortunate in the fact that our Graysee only barks at people who come to the door. She will leap off my lap, or out of her bed, or wherever, and rush to the door, spin a couple of circles, and stand there barking, looking for me to come to the door and open it, so she can then walk (not run) out to sniff the visitor's shoes or pant leg. Once she does that, and sees that it is: A) someone she knows, or; B) someone that I'm OK with, she won't bark anymore. But getting her to stop PRIOR to all that, is almost impossible. The only effective thing I've found is to roll up a magazine or a newspaper; once she sees me doing that, she will become very docile. That stems from her puppy days, when I did the same thing to interrupt her outdoor barking through the fence at the neighbor dogs. I never hit her with the mag/paper, just smacked it against my leg so the loud noise startled her. Then I could get her attention and teach her "NO BARK"! When we're indoors, and she hears a "strange" sound from outside, she will perk up her ears, and begin emitting a low growl, and unless I stop her and tell her "SSHH, It's OK", she will get more aggressive until it escalates into a full bark. Usually I can get her to quit with just a finger in the air, or the command "NO BARK", but the door bell or door knock inevitably gets her up and to the door, vocalizing all the way! On walks, she NEVER barks or growls at other animals, or people, but this past Christmas season, she DID growl at a plastic Santa in a neighbor's yard!