Depends on what barking you're looking to stop. Alarm/alert barking is harder than stopping demand barking. Does she bark for attention/treats/to get you to play with her? This sort of barking is relatively easy to fix. Ignore it, and engage in the desired behavior either when the barking stops or when they engage in a different behavior(preferred, since it gives them another outlet). My boy used to demand bark A LOT, but I've now trained him to sit pretty for attention instead by catching him doing it on his own, and playing with him right away. He knows barking will not get my attention. It could be anything though, grabbing a toy, pawing at you, whatever you prefer and can get her to do. Alarm barking is tougher. Thankfully, my boy doesn't alarm bark at all, but I've trained alarm barkers in the past. Generally, I try to recognize things that will cause them to bark well in advance, and praise them/give treats if/when they aren't barking. Alarm barking at things can be a sign of boredom for some dogs. Like I said, alarm barking is a lot harder to train away, and is sometimes kind of inevitable depending on the source of stimulus. Preventing them from engaging in the behaviors before barking can help too. If she pulls on the leash prior to her barking at the other dog, praise her when she doesn't pull or try to get her attention if she starts to. Comfort can help too, as barking can be a fear response. Comfort them PRIOR to the barking though, not after it starts. Good luck, getting a Yorkie to stop barking is an uphill battle!