Indeed, it's got to the point that the dog is still barking some five to ten minutes after the visitor has been welcomed inside. This is rather embarrassing, especially when friends call round for a coffee and you can't hear each other talking because of the dog barking. Out of desperation, you gave the dog a chew to occupy his mouth, so he can't bark, which seemed to work.
However, one friend who is also a dog lover, tactfully pointed out that giving the dog a chew to quieten him, could be misunderstood by the four-legger as being rewarded for barking. Thinking things over, you realize they have a point. But this now leaves you wondering exactly how you do stop the problem barking.
When you have a puppy, this is a golden opportunity to avoid certain pitfalls that accidentally reinforce barking, such as telling the dog off when someone calls at the door. A great strategy with a puppy is to acknowledge that he's alerted you to the visitor by saying, "I got this, thank you." Then the pup knows his bark has been acknowledged and he can stand down from guard duty.
For the adult dog, things get more complicated as the behavior can be deeply ingrained. But don't worry, with consistent practice and plenty of patience, you will both get there.