Based on a question posed at the KerryBlues-L Newslist.
Someone wrote: "We are the proud owners of a 7 year male kerry, Murphy is a lovable hand-full. He is very territorial, people cannot enter our home unless he is locked in a room alone. Murphy is wonderful addition to our family, I need some suggestions on solving his aggression problem."
There are a number of things you might try with Murphy, but I do not recommend locking Murphy in a room alone when visitors come. I've heard from independent sources (including a Rottweiler breeder) that this is, in fact, a technique to MAKE a dog aggressive, often employed for training guard dogs to attack. Kerries, of all breeds, want to be in where the action is and know what's going on. Shutting Murphy away when there is something going on in another room will only provoke anxiety and increase his sense of possessiveness of his home and owners. Besides, he's not learning anything in there. He needs to learn to behave properly.
There are several things to try.
First, make sure Murphy knows his obedience commands cold. When you say "Down," Murphy's belly ought to hit the floor nearly before the word is out. He also needs to immediately obey the Sit, Stay, and Quiet commands. This training teaches him to respect you as the boss. No need to be harsh about it either. Positive reinforcement (praise and treats) work much better than corrections. If you aren't sure how to accomplish this, enroll him in a class with an instructor whose methods are reward-based.
Secondly, here's a technique to try that I use with my own unpredictable 9-year-old bitch who has a similar problem. When visitors come, leash Murphy and remain seated with him a bit apart from the group. (It helps to have someone else admit the visitors.) Make him sit or down, but keep him near you until he settles down. Advise the guests not to approach him, but let him come to them later on his own terms. After 15 or 20 minutes of calm behavior, allow Murphy (still on lead) to approach the guests if he wants to, sniff them, and "meet" them in his own way. You may ask the guests not to pet Murphy, if you feel that's best. By this time, Murphy will understand that it's OK with you that the strangers are there, and that everything is OK.
Recently, I had a guest come with a pocketful of small dog biscuits. When my bitch approached him, he gave her the down command. She obeyed instantly and was rewarded for her good behavior. If Murphy is food-motivated, you might try this approach, too.
Thirdly, consider using a Gentle Leader on Murphy, rather than a choke chain or pinch collar. A Gentle Leader is a head collar that allows you to control the dog by his head rather than his neck, which is more effective. I have a hard copy of an excellent article on these types of collars that I'd be glad to snail mail if you send me your address. It's best to have an expert demonstrate its use before trying it yourself.
Finally, I highly recommend getting a copy of Dr. Nicholas Dodman's book, "The Dog Who Loved Too Much." The author is a dog behaviorist, and he describes all types of aggression problems that he's encountered in his practice. It's a very readable book and contains a lot of insights into why dogs behave as they do.
In the meantime, I wish you much luck with Murphy's training. I tend to think that this type of problem is not all that uncommon in the breed. Kerries, being devious Irishmen, take advantage of every situation and would run the whole show if we let them. Murphy needs a reminder that you're in charge, and he needs to know what behavior is expected of him.