For those having disciplinary issues with their dogs I highly recommend watching the Dog Whisperer with Cesar Milan - he is a genious when it comes to calming/training pets.  His methods that we have chosen to implement have helped us tremdously getting our dog(Violet) under control.  I've seen him get Pit Bulls/Rotweillers etc etc under control in about 2 weeks.

She is a mix of Austrain Shepherd/Schnauzer - very protective within a week of owning her.  All was cool till a "gang" moved in & verbally threatened me & the dog.  We had a couple of weeks where anytime she saw a black man(no offense) she would go into the Red Zone/Attack mode.  His methods of getting dogs under control are fabulous - but just as a child you have to be consistent.  For her we had find had find willing black males that would help us retrain her.  So, 2 weeks later she is almost back to normal.