What do you do when he barks?
I basically started by when the dogs barked I would call them away from the front of the house where they were barking for a treat and we would do some obedience for more treats. The idea was to interupt the barking. After a few times, the moment I called they would all come rushing to find me where ever I was. Now every once in a while I give them a treat so that they will continue to do it.
I've dealt with some border collies who would just stand and bark at you. For some of them, we would turn out back and ignore them until there was a single moment of silence, then click and treat for the silence. They got the idea quickly that no attention when you bark but for being quiet you got rewarded. The trick here is that after they learn it, you should still intermittently reward them for being quiet.
For another dog our solution was to have him do a long down. He got so bouncy and excited at the front window, he needed to calm down. The owner had him drag a leash in the house (under her supervision) so that she could guide him away and into a down when he started barking. He got a treat for going down and then intermittently. After about a week and a half he figured out the game and when she came in to do the quiet down, he would drop down for his treat. Eventually, all she had to do was ask him to come to her and he would down and get a treat some of the time, but not always.
You can see all of these end with variable schedule reinforcement so that the dogs continue to be motivated to do the alternative behaviot. In all of them, the idea is to interupt barking with something that is more rewarding.
For dogs who find barking in itself rewarding, you may have to find a great treat or game that they really, really love and that may take some thinking on your part.
