I have a book by Victoria Stillwell "It's me or the dog", she also did It's me or the dog USA on TV. The "Stay" command.
((The secret of teaching your dog to stay is not to move through the stages too fast. Build up gradually, both lengthening the time and distance. unlike other commands, you can repeat the STAY command without undermining the training. That's because you're not asking your dog to take a specific action, and to take it promptly. Instead you are asking the dog to do nothing at all.
Put your dog in the sitting position and stand infront of him.
Put your palm near his face and say STAY, wait a second and reward.
repeat and gradually lengthen the time between command and reward until he is staying for ten seconds.
Then you can take a step back. If your dog moves to follow you, give a correct "UH OH"! and try again.
Slowly lengthen the distance between you. Always go back to the dog and on't praise or reward him until you are physically close to him again. praising from a distance will only encourage him to come to you, which undermines what you are trying to teaching him.))
Hope this helps 