Sometimes it is just as important as how you introduce as well as where and when. Dogs go for scent first so when at all possible introduce side to side or butt to nose. Are these friends dogs or dogs you meet on the street. If it is friends try introducing on neutral territory outside if possible and take for a walk where they can not see each other than as time passes move them closer to one another and keep walking. If it is dogs on the street, I would try to have your dog in a sit stay and let the other dogs walk by use treats and lots of praise, when they get the hang of this than let them approach the other dog. Remember your attiude is just as important so try not to anticipate a problem but a good situation.
