Knowing your current dog's personality, likes, dislikes and energy is important when choosing a playmate. Choose a dog or breed that is similar to your current dog regarding activity, training and other qualities.

When adopting another dog from a shelter or rescue, find out if that dog has been socialized with other dogs, kids, cats and human gender. If the dog does not have this experience, or the history is unknown, it may be best to select another dog with better social skills and a known history. It's easier to work with a dog, if you have an idea of their level of tolerance for other dogs and beings they will encounter in your home, neighborhood and other social areas.

Even if your current dog is well socialized, you still need to be prepared for a certain level of territorialism. Dogs don't like it when a stranger comes to their town, especially one that will eat, sleep, potty and seek to share the attention of their pack.

One of the best methods for introducing two dogs to each other, before they enter the home, is to take them for a walk together.

• Standing rigid, tails or hackles (hair down ridge of back) up.
• Standing on tip-toes, as if to tower over each other.
• Mounting and humping.
• Side stepping or rubbing their butt at the head of the other dog.
• leap-turning or bowing. This is a sign that the pup doing it, wants to play.

The most important in that order, is you! Always maintain control, especially with your dog, using positive reinforcement happy tones to let both dogs are doing good.

Some things to watch for, that indicate potential issues, are low growling, snarling, lip curling or overly intense staring (head down, eyes up, with extreme body rigidity). If these occur, redirect your dog's attention with commands, and try again, but with a little more distance between them. If the same occurs, it is likely that these dogs will NOT get along, and it would be best to select a different dog.

Keep in mind that even after the initial introductions are complete, you've taken a nice long walk, and the dogs are getting along great. You still need to keep a close eye on things at home. The process of acceptance takes time.

While the initial introductions go great, and are a great indicator that they will get along; they will still have other obstacles to encounter together, such as toys, food and your lap. Having command over your current dog, regarding ownership and domain, will go a long way in helping the new dog learn what is and is not acceptable.

Be firm with your being the pack lead, but also be fair. Ensure that you are not only reassuring the new dog that his new home is "their" home, you need to assure your current dog, that they are not being replaced.

Make sure that when the new dog takes your current dog's favorite toy, and there is a fuss, that you have an alternative toy to give to the new dog, and give favorite toy to it's rightful owner. Let your dog decide if it's okay to share. If they decide they don't want to share anything, take it all away and work with both dogs in appropriate and acceptable behavior with toys and other property. Give them each some "me" time, where they are not competing for toys and attention, and slowly bring them together for mutual play.

Once your muzzled dog is no longer showing signs of aggressive or defensive nipping, keep them leashed, and remove the muzzle. If they show any signs of this being a "go" for nipping or growling, replace the muzzle until they refrain from these reactions.

Eventually, a dog will realize that they have little to fear or little need to protect themselves and find that playing is much more fun without the muzzle. We have found that with our own dogs, just showing them the muzzle, when they show even the slightest signs of dominance, will stop them in their tracks.

Dogs that are submissive will tend to roll on their backs or lick the dominant dog. This is normal and a part of figuring out pecking order. Even two dominant dogs, pictured left, will sometimes take on the submissive roll, to show acceptance and nurturing with each other. But, do not panic if they get into a tiff now and then. Just be prepared to intervene when playing gets too rough, as sometimes this tends to turn into pecking order play, and can end up turning into growls, snarls and fighting.

The key is to not allow unsupervised play or interaction, until you are confident that both dogs understand who the boss is; YOU! And, NEVER separate dogs that are fighting, with your hands, you may get bit.

A little dominance is okay, as each dog figures out what each others space is, and where the line in the sand is drawn in acceptable infringement(s) on the same. But it is ultimately up to YOU to define the rules of the playground and at home.

With puppies, they tend to pester adult dogs. Your adult dog may give a warning snap or growl. This is okay, as it's natural for older dogs to put younger dogs in their place. It becomes a problem if the puppy does not take the cue and continues to pester. In this case, you may need to separate the puppy, to give your older dog a break, and prevent the puppy from getting hurt. Never leave a new puppy unsupervised, until you know they are not in danger of getting hurt. This would be a great time to start them on command training.