This is one of the TOP things I'm going to focus on when I get my yorkie. I have a beagle and she is wonderful, super sweet and not aggressive at all (it's funny - she prefers the little tiny dogs way more than the big dogs cause they don't overwhelm her - we even took her to the tiny dog social group at doggie daycare cause the employees recomended it, ha!) but she is shy in public (she shows interest in dogs and people but it's very overwhelming for her). So I'm going to take my yorkie everywhere and introduce the yorkie to all kinds of different people and dogs, sounds, places. We're working on conquering Shelbie (the beagle's) public shyness. So we want to just start from day 1 with the yorkie and work really really hard on taking her to as many places as we can. It's a MUST in my opinion.
I'm actually most excited about that aspect. I want to mold my future yorkie to be very comfortable and confident.
(This is like having a child, isn't it? Ha)