How do you train a dog to not bark when the door bell rings?

The key to training a dog to do anything is repetition. If your dog is one of the few that doesn't bark when someone knocks, don't worry. You should be able to train him or her to do so in a short amount of time.

The first thing you need to do is train your dog to speak on command. A simple way of doing this is to restrain your dog, in a safe way, of course, and call his or her name. When they get frustrated because they can't get to you, they will bark. Once they bark, you need to immediately praise him or her and give a treat. Continue this until you can get the dog to speak without being constrained.

Then, use the speak command when someone knocks at the door. You may want to get someone to help you for this part. Every time the dog barks at the knock on the door, give praise by you and your helper.

Your dog will quickly learn to bark when someone knocks.