Introducing A New Dog to A Home with Resident Dogs

Renee DiPietro, LVT, Permitted Wildlife Rehabilitator
Veterinary Information Specialist
Pet Poison Helpline®

Initial interactions between resident dogs and new canines can be unpredictable. For this reason, such introductions should be approached with caution and planning. As with people, first impressions are important and can set the stage of a relationship between pets residing in the same household.  There are a variety of possible scenarios that are dependent upon the age, species, temperament, pecking order status, etc. of the animals to be involved in the introduction.

If your current dog or dogs have a history of fighting with other dogs reconsider your choice to take on an additional canine family member. The happiness of your current dog may need to negate your desire to have another pet.

If you are not willing to consider keeping your dog a solo pet it would be wise to speak with an expert in canine behavior and implement the suggested behavior modifications with your dog(s) before attempting to add a new member to the current canine or pack already established in your home. Your dog(s) considers your home to be his den. That natural territorial component combined with a history of aggression towards other dogs could set you up for a dangerous situation if these issues are not dealt with proactively.

Tips for less than confrontational introduction:

  1. Leave your current dog at home when you go to pick up your new dog. This is a safer idea for everyone involved. Managing the interaction of two new dogs while you are driving a car will not be possible and the confined space could make the initial meeting more fractious.
  2. Recruit a helper(s) for the introduction. You should have one person to handle each dog.
  3. Choose a neutral setting for the meeting. If you bring a new dog into your home before it has been introduced to your current dog(s) there could be territorial behavior that develops into aggression.
  4. Keep the dogs leashed initially, but try to keep a loose lead to reduce tension. Allow interaction between the dogs to progress at its own pace. Even if they ignore each other at first this is better than forcing them into a situation that causes them to become defensive or aggressive.
  5. Keep initial interaction brief. Allow them to touch noses, sniff each other a bit, then separate them and involve them in another activity such as obedience exercise or play for a few minutes and then allow them another short introduction. This fragmentation of initial contact can help to prevent escalations of tension and aggression.
  6. Keep your own voice and attitude and those of the other handler’s positive and happy. This will help to keep everyone in the situation, humans and dogs alike, calm and productive.
  7. Have treats handy and use them as rewards for good behavior during the interaction breaks. Do not offer them while the dogs are interacting.
  8. Observe the body language of all dogs involved. If your new dog is being introduced to more than one resident dog, it is really best to make separate introductions so that pairs or groups of dogs are not ganging up on the new comer. Inviting, happy body language is a sign that things are going well. Guarded, defensive body language can mean trouble. If negative body language is observed, separate the dogs and return to distracting them with other activities. Wait a little while and then try again but keep the interaction very brief. The main goal here is to prevent escalation of tensions between the dogs.
  9. Continue with brief interactions until the initial excitement has worn off and greeting behaviors have dissipated. When everyone is behaving in a calm and positive manner it is time to take your dogs home.
  10. When you arrive at home take your dogs for a brief walk around the neighborhood together before approaching the house.
  11. Once you have entered the house lead them around the inside of the house together. If they accomplish this calmly, let them off the leash but keep them where you can supervise them.

During the first few weeks after bringing the new dog home, nurture this blossoming relationship.  Make sure you have removed any toys or personal items belonging to you current dog(s) before introducing the new comer. The idea is to remove any impetus for conflict.

For the first few weeks each dog should have a separate area where it is confined for sleeping, meals, time- outs, and when there is no one home to supervise. This can be accomplished by crating the dogs or keeping them in separate rooms. After a few weeks if everyone seems to be getting along well you can start to leave the dogs together without supervision for short periods of time.  If all seems well with them, slowly increase the length of time until you feel you can trust them for longer periods without mishap. Do not ever leave them unsupervised with food available to them.  Eventually you may be able to feed them in the same area if you teach them manners for this situation. If food is left in the bowls by any party pick it up and offer it again later.

During these first few weeks it is also a good idea to introduce variables into the interaction periods.   Have people come to visit, and other families interact with the dogs during their together time.

If there appears to be any ongoing tension between the dogs keep their periods of interaction or hanging out together brief. Halt any escalations of temperament with a firm, consistent command and then separate them for a short period.  When they behave well together praise them equally.

If despite your best efforts tensions between the dog members of your household persist or escalate, contact animal behavior expert for advice. This help could come from a veterinarian, veterinary technician, dog trainer or animal behaviorist.

In the event that a dog fight should occur you must stop it to prevent further injury. This being said, never, ever, get into the middle of it. Try distracting the dogs with a loud noise, if this does not work you can throw something soft such as a couch pillow, a soft plastic dog dish, or a coat at them, or if outside spray them with hose. Once they are distracted for a moment get a hold of at least one of them and separate them until they are calm. This does not mean they cannot be introduced again but they need to be kept separate for a short time until tensions between them have eased.

If the new inductee is a puppy, some slight variations to the above guidelines may need to be implemented.  Puppies are exuberant in their actions and interactions and are not often experienced enough to recognize and consequently respect the warnings of older members of their species.  This is a good reason to leave puppies with their mother as long as possible as she will teach them species specific manners and the ins and outs of interacting with their own species.  If you have the choice of taking a puppy from its mother at 8 weeks, or 10 or 12 weeks, go with the longer period. Just a couple of weeks can make a huge difference in teaching a puppy positive social interaction within its own species.

Click here for an article containing tips on how to introduce a puppy to older dogs.

Dogs are communal animals and generally enjoy the company of others of their species. If the initial introduction period is managed in a calm, well planned manner, your new family member will likely bring much joy to all of your human and canine family members.

In rare instances, your dogs may not may not achieve a relationship in which they can be trusted to stay alone together or even to tolerate each other for more than brief periods. Be willing to accept this possibility and have a plan now that you have committed to this new family member. There are creative ways to live with dogs that cannot get along.


  1. Dog Time
  2. Pets WebMD
  3. Clicker Training