My dog does really well the dogs in the family. She is completely submissive. We laugh because when one of the other family dog's come over, Misha throws herself on her back and lifts her legs as if to say "Go ahead, smell me." She is a bit timid around the other dogs and doesn't really play much with them. But, we haven't had any fights.
It's a different story when we our in the neighborhood. We've had several incidences where dogs have gotten loose from their homes or their owners and run at us. So, Misha has gotten somewhat protective when approached by strange dogs. She is ready to fight them off, which isn't good, since she is only 9 lbs.
On the other hand, I have worked hard with her at passing dogs that are on leash with their owners when we are walking. I am happy to say she does this very well now. She might show interest, but for the most part, I can get her to walk by. A year ago, she would have barked and snarled. Progress is slow, but she keeps getting better as time goes on.