Hi maggie01, I have a little shih-tzu and he walks on the Burrows near our house that has about 50 horses and hundreds of sheep running free. He meets all sorts of dogs there and has never had any problem with any of the lurchers we meet. So I don't think you will have much of a problem. Quite often it is the smaller dogs who take charge in a house hold of mixed sized dogs. I had Irish Wolfhounds in the past, a St. Bernard and an Irish Setter. All of these were really great with small dogs. Congratulations on your puppy maggie01. I know I am always saying this, but when your pup is old enough, please do take it to puppy classes (preferably clicker classes). You will end up with a gently trained, well behaved dog that will be a joy to live with. Best wishes. :o)