The freeze and stare or stiff body and tail held high are serious warning signs. These dogs are telling you to back off or they may bite.
On the other hand, if a dog’s whole body is wagging and he is panting it means he is happy and it is probably safe to proceed with introductions. Just bear in mind that a wagging tail is not always a sign of friendliness, it could just mean that the dog is in a heightened state and may be nervous.
If we are careful and pay attention to the signs, we should be able to interact with most dogs and safely allow people to meet our dogs. But, as long as a dog is fearful enough to feel the need to protect himself, a dog bite could occur.
If you are concerned about dog bites, here is an excellent video, well worth the time it takes to watch. http://thegreatdogadventure.com/episode27/
In the end, it is up to us to watch and read our dogs’ body language, but ultimately, it is not what our dogs do that matters, it is what we do to protect them.