Whew! There's a lot of food for thought! I am still looking into outside help. I have ordered some of the suggested books. I will check out the websites noted. I have tried several of the suggestions to ignore my dog and guess what? I have not been growled or snarled at for two days now. Mackenzie really, really, really doesn't like for me to ignore her. She's very much looking for recognition from me. It's very, very hard to do, as several of you have noted. I know it is not the complete answer, as I need to find out why it happened and reestablish my dominance, and I will be working on that on all possible fronts and will keep y'all posted. Thanks to all of your for your suggestions and concern - I have been really touched by all the help.