Boundaries; we all have them, as adults and children and dogs. An environmental boundary can be anywhere; you just have to choose it. Teaching boundaries is fairly easy but without consistency; you'll have a challenge. One thing about boundary training is there is no command for this exercise. We want your dog to know that it is absolutely not an option to cross a boundary; especially out a door on their own. If someone should happen to leave a door ajar your dog should know that they just don't go out, without you telling them that they can.
The first thing you need to establish for yourself is what boundary you will train. Even if you have several areas you want to teach say like the front door, side gate and garage door only work on one at a time. Once that is trained it is easy to train a new additional boundary.
Now you need to make sure there is a clear boundary for your dog so that they can understand. It may be a front door mat, the actual door or a change in flooring. Once that is decided and you have a clear view of where your boundary is, get your dog. Put a leash on your dog so that if they cross the boundary you have something to grab onto and if your dog is a guaranteed bolter, get a long leash on them and tie them to something, leaving the leash long enough for them to cross the boundary. Get some treats, small ones like the size of a dime (charlee bear treats) work great for this.
Start out with your dog behind you and behind the boundary, walk towards the boundary. If they try to follow you over the boundary you turn and walk abruptly into them. Body language is important for this exercise as it helps your dog to understand right from wrong.
Once back over the boundary you turn and try again. If they do not attempt to follow you quickly throw a treat back behind them. You want the treats behind them because you do not want them coming to you to get the treat. Make sure to reward the smallest of success, this helps them to move on more quickly.
Now try to walk over the boundary and touch the door handle, always be ready for your dog to fail. You must act immediately turning and walking into them. Dogs really do not like when you walk into them so this is a very good message to keep them back. Do not use words, you can use sounds as I find it nearly impossible not to grunt some displeasure to my dogs and use happy sounds for their success. But you are not going to tell them to stay, they are not staying they are just not to come over the boundary. (More on stay in the future)
You are going to make it harder and harder but in baby steps. Now try to open the door, always keeping one on eye your dog. Do this exercise in a very fluid motion, do not hesitate and move slowly or it is a very unnatural behavior from you.
Treat for success, move in and walk at your dog for failure. Only move to the next step once your dog succeeds.
When you need to get your dog back over the boundary it must be done quickly, calmly and with purpose. Walk into them and once they are over the boundary turn around right away and try again. You have your dogs attention right now, use it.
I'm sure you get the drift of the exercise now. You are going to push it and try to take a step outside and then back. Once you can do that, pretend to talk to someone outside (this almost always creates a boundary break so watch). Then you are going to start hanging around outside, don't forget to treat for them NOT following you.
Treating is to get the message through quickly and clearly. Depending on the level of your bolter and age will be how long and how often you treat. My dogs never get treats for this now but they sure get happy talk.
The boundary you set is for when a door is open, if a door is closed a dog can cross the boundary at will. This is something you cannot always be on top of so futile to try.
When it is time for your dog to go out the door or gate or whatever you must make it very official. They are only to ever go out with one word. It makes no matter what that one word is but they must hear it before going out. Push your dog with this exercise, practice lots of different scenarios that you think might have your dog break a boundary. The more you train the more your dog will be ready for the real thing.