Skittish Pit Bully puppy

Question
My Fiancee and I have had our wonderful puppy, Noodle for the past year. For the most part, she is the most wonderful dog I have ever owned, and she has no prior aggression or fear issues, since we are her first owners. She behaves wonderfully around anyone she knows, especially when she is in her "comfort zone", e.g.- the house in which we live and the surrounding area. The problem with which I come to you is this: as soon as a person to which she has not been introduced invades that space, her personality seems to completely change, and the loyalty she displays toward us turns to a fierce protection for our safety against some imagined threat.  This, to my fiancee and I, seems like the type of behavior exhibited by a dog who has been specially trained in this function, but this is certainly not the case. She has almost bitten people on more than one occasion, but has never actually done it. How can we break her of this habit before it becomes a real problem?  Thank you so much!
 -Josh, Christie and Noodle

Answer
Hi Joshua, Have you taken Noodle to obedience training? If not, you may want to do something I do in my home where we live with three large dogs who want to protect us with their lives, but must behave since we give lessons, and are certified Service Dogs. We ask all of our guests, friends, and relatives to knock before entering and wait for us to open the door. I allow the dogs to bark three times, then give them a hand signal (which is like a peace sign against the front of my chest or neck) and say, "Come Back To Me". This takes some practice. Once they all come back to me, I praise them for protecting me and tell them to sit/stay or down/stay until I open the door and invite the guest inside. They cannot break the sit/stay until I take the guest to them and let them smell the top of their hand, fingers curled under, with the guest not looking the dogs in the eyes and their hand goes under the dogs snout. At that point I say "Okay, Friend", if it is someone that I want my dogs to accept, or simply "Okay, good protect" if it is a stranger that I want them to keep an eye on. Noodles will learn from the way you and your fiancee respond to the guest, as to whether they should watch them or become friendly. Once you release them with the "Okay", they are free to move about the home, but never allowed to jump up on the guest or pester them in any way. Give it a go and let me know how it works for you. Please leave me some feedback, nominations if you wish, and keep me posted. The only way we can tell we are doing a good job, as volunteers, is by your feedback or reposting us. It is much easier to see results in our classes, and we can correct problems so much easier. So let me know how it goes with Noodles as soon as you can. I realize it may take some time to teach her, but let me know. I really care about the outcome and if you have any problems, feel free to ask any other questions you may have as you go along in her training. Thank you for writing. Regards, Susan