[SWHouston]

I may not be the just the right person to be advising you, since I support this type activity, BUT, with my Males only.

I think that Yorkies in general are quite, one Person orientated, protective and territorial. So, it's not hard for one to migrate toward an intense need to do those things.

However, my Females are not that way (as much) and I think it's because I continually expose them to strangers/situations, where they become more acceptant to what the Males consider violations. In fact, when I have guests over, I put my Males up in their room, and allow the Females to socialize. I want to maintain this strong difference in their demeanor.

It's possible that more frequent exposure to strangers with appropriate verbal corrections, or, Obedience Training may be avenues.