I recently acquired a 17-month-old Rottweiler who came into my work to be euthanized, as he was apparently aggressive with other dogs and has had 5 homes since 30/09/09. I thought I would give him a chance, so I carefully introduced him to my small pack of dogs - two Rottweilers, a Labrador, a Springer Spaniel, and a Lhasa Apso (all of whom seem to have calm states of mind).
He has been absolutely fine with them all, although he occasionally mounts a few of them (despite having been recently sterilized). So, when he does that, I come between them and give his shoulder/neck area a firm touch. He has been fairly submissive, and lies on his back.
Also when we are out walking and he sees another dog, he tries pulling me towards them. I recently bought him a Halti, and he seems to be getting better. I walk confidently past the other dog, and I try and make sure the lead is not tense.
I have them in a set routine and on the weekends, I walk them for miles and they get to run off-lead through the fields to help burn off some energy. I recently bought a pair of roller blades and take them round town. God, it's hard work - I thought they would pull ME! :) They love it. You're a Legend!!
Lynlea Cottage, Peterhead, Aberdeenshire, Scotland