Introducing Dogs to Each Other

Dogs are social animals, and many enjoy the company of other dogs. However, introducing a new puppy or dog into the family can be tricky if you already have a dog. The resident dog may not be accustomed to having other dogs in their home or they may not appreciate having to share your attention. First impressions are important! Follow these tips to maximize the chances that your introduction goes smoothly.

If your dog has a history of fighting with other dogs, please consult with a Veterinary Behaviorist or Certified Professional Dog Trainer before introducing your resident dog to a new dog.


Before you bring the new puppy or dog home, remove anything your dog might not want to share with another dog, such as food bowls, bones or chews, toys and beds. Even if your dog has never shown aggressive behavior when approached while in possession of objects or food, it is best to exercise caution. Tidy up your living space as much as possible, as open or airy layouts or living spaces are ideal when acclimating your dog to a new dog. Congested or narrow areas are more likely to trigger aggression, as the dogs are forced closer together than they are comfortable with.  

The First Meeting

Have a family member or friend help so there is a person to attend to each dog during the initial meeting. Make your way, separately, to a neutral area. An open area in a park is perfect because there are plenty of interesting sights and sounds to distract the dogs and space to move away from each other if they choose. It is best not to introduce the dogs in the house or yard because the resident dog may become territorial. If you have multiple dogs, introduce each dog to the newcomer separately before bringing everyone together as a group.

When you both arrive at the neutral area, bring the dogs together and allow them to greet each other.  Keep their leashes as slack as possible while they do their initial greeting sniff, as tension in the leash can cause scuffles. A puppy will typically adopt a submissive position: lying down or even rolling over to be investigated by the adult dog. A well-socialized adult dog will likely check the puppy out and then either play with it or ignore it. When two adult dogs meet, they often stand tall and “posture” to each other. They will sniff each other, they may circle, they may urinate, they may bow toward each other playfully, or they may decide to ignore each other. Don’t panic if they push each other a bit, growl, or even try standing up on each other’s shoulders. Allow them to interact with as little intervention from you as possible.

The exception to this is if they try to fight. If the dogs become tense with each other (raised hackles, growling, showing teeth, prolonged stares, snapping, etc.), call the dogs away before things escalate. Try not to pull them away by the leash—added tension on the leash might trigger an attack. If the dogs won’t come away on their own, wave a super yummy treat in front of each dog’s nose and then lure them to turn away from each other. Make sure to keep your body language as relaxed as possible and remember to breathe! Dogs can read tension or anxiety in your body language, and it can affect their interaction negatively. If the two dogs attempt to fight or have a negative interaction, we recommend reaching out to a behavior professional for assistance in any further introductions. Keep the dogs completely separate utilizing crates and/or securely installed gates until you are able to obtain professional guidance.

Keep the interactions brief at first. After the dogs greet, go for a walk together. Parallel walking takes some of the pressure off the dogs because they can sniff around and do other things. Additionally, you could offer the dogs a yummy treat each time they look at the other dog, to help further associate each other with good things.

Bringing the New Dog Home

Walk home from the park with the dogs together and just walk into the home as though nothing has changed. If you have a yard, go there first and let the dogs off leash to hang out in the yard, supervised. Periodically call the dogs away from each other, if they are playing, and reward. Let them play for a few minutes, or coexist calmly if they are not playful, before bringing them inside. Bring the new dog inside first, on leash, and permit the new dog to explore the room/house. This is a good time to double check that no toys or food were left out! When the new dog seems relaxed and is done investigating, bring in your resident dog on leash. Reward each dog for looking at each other and remaining calm. If both dogs are acting calm, let the resident dog off leash first, followed by the new dog if the resident dog continues to act in a friendly manner.

It is vitally important that you actively supervise all interactions between the dogs. Don’t leave them alone together until they have had no tense or negative interactions with each other for at least one week, though some dogs may need longer. Keep your routines (mealtime, bedtime, walks, playtime, etc.) the same as before the new dog arrived, so things don’t seem too different for the resident dog. For the first few weeks, keep an eye on the dogs in situations that might trigger aggression, such as when you come home, when guests come to the home, going out to the yard, coming in from the yard, preparing to go for a walk, mealtime (theirs and yours) and playtime.

It is very important that you spend time with each dog alone so that the resident dog continues to receive one-on-one attention and the new dog develops a bond with you. If you only hang out with the dogs together, they may become attached primarily to each other, rather than to you. The new dog needs to bond with you.

Extra Tips:

  • If you are bringing home a puppy or small dog, do not hold them in your arms for your resident dog to greet. This may cause the new dog to feel trapped and threatened. Instead, stand with your feet slightly apart so the new dog can take refuge between your feet if they feel overwhelmed. Do not permit the resident dog to trample, bowl over, or otherwise intimidate the new dog.
  • Don’t put the dogs in small spaces together, such as in the car or a small room, until they are completely comfortable with each other. Dogs should never be crated together.
  • Each dog should have its own food bowl, crate, bed, and toys. Place the food bowls far apart, or better yet, crate the dogs separately during mealtimes, with several feet between crates. Do not allow one dog to intimidate the other so that it abandons its food.
  • If a fight occurs, DO NOT let them “fight it out.” While this is popular advice, permitting the dogs to continue a fight can set the tone for a difficult relationship. Interrupt and separate the dogs if they begin to fight or if one dog bullies the other dog. It is always better to interrupt fighting so the dogs do not develop a pattern of aggressive behavior.
How should dogs that are fighting be separated?

Get the dogs apart however you can, while doing your best to not be bitten in the process. It is quite common for owners to be bitten breaking up a fight, often by their own dog.

Your first action should be to shriek and yell—this works with many dogs. If you have pots and pans nearby, try banging them together to make a loud noise. If the dogs are on leash, pull them apart but be aware that you may inadvertently cause the dogs to injure each other more because they tend to clamp down with their jaws to resist the pull. If the dogs are off leash, try getting behind them, grabbing them by the hips, and lifting each dog’s hind end off the ground. Sometimes, the feeling of being airborne causes the dogs to stop fighting. Be very careful because this strategy places you in a vulnerable position! If you can’t grab them, try pouring water on the aggressor’s face or spraying the dogs with a water bottle or hose. Other options include an air horn or Direct Stop citronella spray. Avoid hitting the dogs because this type of pain often escalates the aggression.

After Fight Care

After a fight, seek immediate veterinary care if necessary. Separate each dog from the other for several hours to allow them to cool down and take steps to reduce their stress during this separation. Long solo walks where you encourage sniffing can be very relaxing for both dog and human. Most dogs enjoy a calming massage, although if your dog has wounds take care to avoid that area as it is likely to be painful and sensitive. Offering each dog solo enrichment opportunities can further reduce stress, particularly if the enrichment is lickable, as licking is a soothing behavior for dogs. Check out additional DIY enrichment ideas here. If the dogs are frequently fighting, or fights result in injuries requiring veterinary care, we strongly advise seeking professional assistance before further attempts to integrate.

Have questions?

Contact our Behavior Specialists at [email protected] or (212) 876-7700 ext. 4971

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