Well, the way I'm doing it with Finn is teaching him to bark when I ask him to, and, he's getting that pretty well. And, then, teaching him to "shh", which he's actually learning that way! He started barking while he was playing with the cat this morning, and, I put my finger to my mouth and told him to shhh...and, he stopped! It's still being trained, though, so, it doesn't work all the time.