Introducing new pets to current pets

Current animals get into a routine of knowing what to expect from you, their caretaker, and your other current animals and may see your home as their territory. When you bring home a new animal, your current pet’s first instinct may be to run away or to fight off the “intruder”. Adding a new pet to your household can be stressful for your resident pet, and may lead to stress-related sickness or behavioural issues due to territorial displays or anxiety. Therefore, it is important to slowly introduce resident pets to new pets. If introductions go poorly, early intervention and advice from a professional is recommended to reduce risk of injury from a pet fight.

You will find the following information below:

Dog to dog introductions

It would be beneficial to read through the page, “Bringing your dog home” , to help you prepare your house, new dog, and resident pet(s) before you introduce your pets.

When introducing pets, pay attention to both pets’ behaviours to make sure neither gets too anxious, fearful, or aggressive during the introduction. You want to try to make sure the experience is a good one! It is important to redirect and encourage dogs to do something else if you notice either dog’s anxiety level rising.

Having tasty treats is helpful for rewarding dogs for good behaviour!

Introductions on neutral territory

Where: Introduce animals on neutral territory such as a nearby park or a friend’s backyard.

When: A couple days after bringing your new dog home and they have settled down in a separate area.

How: Have each dog held by a separate person*

*NOTE: the use of leashes and head collars may prevent dogs from showing normal body language. People often get nervous about dogs meeting for the first time and tug on the leash which can greatly influence the dog’s behaviour and reaction to the other dog. Therefore, it is recommended that loose leashes be used for introductions. This will allow the dog to show its normal body language while still allowing the owner to have control if necessary.

Steps to introduce pets:

  • 1.

    Have both dogs a moderate distance away from each other so that they can see the other dog but still remain calm. Give the dogs treats for remaining calm.

  • 2.

    Give the dogs commands to make sure that they are still listening to you. Reward the behaviour once the dog does what was asked, such as “sit”, “lie down”, or other simple commands. Rewards can include treats, petting, and/or praise.

  • 3.

    Bring the dogs slowly together; stop every couple feet to ask a simple command and reward the dogs for listening.

  • 4.

    If the dogs seem comfortable with this, walk the dogs close together so that they may just sniff each other’s noses, and then walk them away after a few seconds. This very brief period of time will help to avoid any tension building. Reward them for their good behaviour as you lead them away.

  • 5.

    You can repeat this again, leaving them together for longer periods of time before walking them away each time. It is important that the time spent together is built up gradually. Monitoring both dogs behaviour throughout these interactions will help to avoid anxious and/or aggressive behaviour. If either dog appears anxious, walk them away, and redirect them using simple commands and treats.

  • 6.

    Once the dogs appear to tolerate each other and the greeting behaviours have faded, it is time to go home. Before taking them inside, walk them together for a little bit.

  • 7.

    After the first time doing this, it may be a good idea to still separate the dogs until another time when you can introduce them indoors.

If at any time things escalate and the dogs begin to growl, snap, or act aggressively, separate them.


If possible, use simple commands to get them to focus on you and reward them for doing so. If a fight does occur, throw a pillow or keys nearby or use a water gun to disrupt the fight. Separate the dogs into their own areas and leave the introductions for another day.

If introductions don’t go well, we recommend getting advice from a professional to decrease risk of injury from a pet fight.

Dog to cat introductions and vice versa

It would be beneficial to read through the page, “Bringing your dog home”, to help you prepare your house, new dog, and resident pet(s) before introducing your pets.

When introducing your pets, pay attention to both pets’ behaviours to make sure neither gets too anxious, fearful, or aggressive during the introduction (so that the experience is a good one!). Distract or redirect the animals to do something else if you notice either’s anxiety levels rising. Observe your cat(s) carefully because their signs of anxiety are much more subtle than dogs.

It is important to not allow dogs and cats to be alone together unsupervised unless you are positive that they will be safe. Dogs can have a size advantage and seriously hurt small or shy cats without meaning to, whereas cats have sharp claws that can do a lot of damage if a puppy gets too close without listening to warning signals.

Having tasty treats is helpful for rewarding dogs and cats for good behaviour!

Reactions you might see when dogs are first meeting cats:

  • Treat the cat like another dog and try to play with them. This can be dangerous because of the size difference (i.e., dogs tend to be larger than cats) and cats’ having sharp claws.
  • Seeing the cat as prey. This can especially be the case if the cat flees; your dog may see your cat as fleeing prey and chase them.
  • Your dog could show interest from afar. Your dog may approach slowly or watch at a distance.

Reactions you might see when cats are first meeting dogs:

  • Your cat could show interest from afar. Cats raised with dogs and/or young or confident cats and cats living in multi-cat households may watch from a distance, or approach cautiously.
  • Defensive behaviour. Many cats do not accept new animals well and consider them “intruders”. This is a result of cats tending to be very attached to their territories.

Before introductions

  • Clip cat nails in case they swipe at your dog.
  • Have a carrier or leash with harness for your cat, and leash with flat collar for your dog.
  • Find a room that has hiding spots or perching spots for your cat.
  • Make a dog-free zone for your cat to relax in if they get too stressed.
  • Train your new pet as best you can, and your resident pet so that they can be redirected (i.e., focus on something other than the new pet).
  • Confine your new pet and allow your resident pet to wander the house.
  • Make sure your dog doesn’t have access to your cat’s litter box.

Swapping scents

Since cats communicate with scents, it is important to allow your cat to get used to the smell of your dog before introducing them.

  • 1.

    It is important to keep the pets separated, with the new animal in their own room with all the essentials (see our 'Budgeting for your pet' page for an initial list of supplies), if possible.

  • 2.

    Take a piece of bedding from your cat or a towel that has been rubbed on their cheeks and place it under your dog’s food bowl. Do the same thing for your dog with your cat’s bedding. Encourage your pets to approach their food bowl. If they show signs of anxiety or aggression, move the bedding/towel away from the food bowl until they calm down. Slowly move the bedding/towel closer to the food bowl every day until you can put it under the bowl without your pet becoming upset.

  • 3.

    Next swap the pets’ empty food bowls; this will help associate the scent of each other with something positive such as eating their food.

  • 4.

    Feeding your dog and cat on either side of a solid door that separates them will allow them to hear and smell each other without becoming overly stressed. First feed them a couple feet from the door, slowly moving the bowls closer to the door. Be careful touching the bowls if either animal shows aggression towards you when you come near their food. If they do, wait for them to finish and move bowls closer at each meal time until they can comfortably eat on either side of the door without looking stressed.

Exploring the house

  • 5.

    As your new pet becomes used to their room, you can start showing them more rooms in your house. Make sure to temporarily put away the resident pet so that your new pet can take their time exploring on their own. Cat-proof or dog-proof (e.g., removing potentially dangerous items that can be chewed and/or swallowed like thread, rubber bands, children’s toys) the areas of your house you will be showing and take them to a different room once they are comfortable exploring these new areas. Don’t forget to give your new pet rewards (e.g., treats, praise) for appropriate behaviour.

Meeting face to face

  • 6.

    Before the introduction, take your dog outside for a run to work off any extra energy. Practice “come”, “sit”, “stay”, “lie down” and “leave it” commands.

  • 7.

    It is important to watch your pets closely and supervise them; make sure that your dog doesn’t startle your cat by keeping their attention on you. Pick a large room and allow your cat to stay in a carrier at a height (either on a table or on a helper’s lap while they are seated).

  • 8.

    Bring your dog in on a leash with a flat collar from the opposite side of the room and stop while still at a large distance from the cat inside the carrier. Remember to maintain your dog’s focus on you by rewarding them for their good behaviour. Have a helper feed your cat tasty treats to maintain a positive behaviour.

  • 9.

    Making sure that both animals are relaxed and calm, begin to slowly decrease the distance. If at any point either animal becomes anxious, go slower, or move back to a larger distance.

  • 10.

    After reaching about a foot away without any problems, take your dog back to the other side of the room where you started. Repeat with the carrier door open, allowing your cat to leave the carrier and explore. Make sure that your dog’s attention is focused on you and that they are still restrained. Provide an escape route (a hiding place or a perch) for your cat to get away from your dog.

Getting your dog used to cats

By rewarding dogs when cats are around, dogs will learn that behaving well around cats means they will get tasty treats.

  • 11.

    Find a comfortable spot to relax with your dog. Have a helper bring your cat into the room but at a distance so that your dog remains calm. As long as your dog can see your cat, feed them extra special treats if they remain calm (e.g., no lunging, barking). If you are worried your dog may run, a loose leash with flat collar is a good precautionary form of control.

  • 12.

    After a couple minutes, have your helper leave the room, taking the cat out of view. Stop feeding your dog the treats.

  • 13.

    Repeat steps 11 and 12 until your dog looks at you for a treat when they see your cat. You can then start reducing the distance slightly.

  • 14.

    Go slowly and increase the distance every time your dog appears agitated. End each session on a good note.

  • 15.

    Once your dog and cat are comfortable to leave their comfort zone and your dog is reliably calm around your cat, you may take off your dog’s leash. You may see warning signs in the beginning (e.g., hissing) as they learn how to act around each other.

If introductions don’t go well, we recommend getting advice from a professional to decrease risk of injury from a pet fight.

Lifelearn. (2014). Introducing a new dog to your family dog. In dog behaviour and training. Retrieved from

Ontario Society for the Prevention of Cruelty to Animals. (n.d.).Helping cats and dogs to get along. Retrieved from