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Animal introductions

Step-by-Step guides on introducing existing pets to new family members



Cat intros take time! It's all about understanding the nuances in their behavior, and allowing them to express themselves in a healthy way.>



Now that Underdog has supervised a dog intro to see if you're dogs are a good fit, here's how to keep the peace in your home without use to supervise. >



Cat/Dog intros are the most intense of the introductions. The most important thing is ensuring safety and making sure we're slowly building the cat's trust, and the dog's respect.>

First things first:

Only proceed to animal introductions if the steps covered in the new cat/dog guides have been completed.

Cats should still be mostly confined to their "home base", and dogs should not have been allowed time out with other animals. 

If you have not completed the steps in the New Cat Guide or the first 72 Hour Guide for dogs, do not proceed with these next steps. Moving too quickly can damage the relationships and make integration much harder.

Do not rush this process!

Cat/Cat introductions

Now that your new cat is starting to feel confident in their home base, these are the next steps to get them ready to meet their feline siblings.


It's important to NOT let the cats see each other just yet. There's a lot going on: a stressful cat carrier confinement, a car ride, a new place. The stress hormones are going crazy, and you don't want them to lock eyes with their new cat roommate and make a bad assumption that this is just one more stressful thing. Give your new cat time to decompress, get the stress hormones out of their system, and to make a good first impression on your existing cat.


After the initial stress of the new transition, your new cat will most likely start to get a bit more adventurous. You may already see them start to sniff around the bottom of the door. Every once in a while, you may be greeted by one of these playful feet:


This is exactly what you want to see- eagerness to learn more, instead of being overwhelmed by all the newness!

Hopefully by now, your resident kitty will have started to get an idea that something is going on, and start to investigate under the door. You can encourage this by feeding meals on either side of the door, giving treats, and generally making this newness a positive. They will make positive affiliations with each others' smells. Sometimes they'll even play footsie under the door, which is great! But don't get over-eager and throw the door open assuming they're ready to be best friends.

When you feel the confident kitty seems to be eager to explore more outside or even to get to play more, this is when we can go on to the next steps.

Pro tip: Positive Pheromone Products

Feliway or other positive pheromone sprays can help cheat the situation in your favor. Diffusers are nice for general destressing, but these products are most effective when trying to make positive links. When you want your cats to make a good association, spray Feliway on a washcloth or rag and put near the cat or cats. The sudden appearance of pheromones will trick their brain into thinking something good just happened. It won't over power other natural instincts like fight or flight, so just know this is a little "boost" to their existing feelings.


The next step is to physically swap the two cats. Put your resident cat into the new cat's "home base" (unless directed not to for medical reasons ie quarantine periods, surgery recovery, etc). Let them have some time to sniff, explore, and really let it sink in that there is another cat in their home. In that same time, you can let the newcomer have a bit of (supervised) time to smell, explore and learn, provided that they are ready for this stage. Don't let them into a larger space if they still seem very nervous- since they don't have their home base to retreat to, they need to be a bit more confident for this!

Repeat this a few times until each cat seems comfortable with the newness. Then you're ready for the next stage of introductions!


Remember how we said not to let the cats see each other? Once they've started to have some positive interactions under the door, or seem less stressed, we can add sight into the mix. Open the door and allow them to see each other, usually with some kind of barrier. We always recommend a flex fence/exercise pen or baby gate to create a physical divider in case one cat makes a run for it, or gets a little too forward. The key to introductions is incremental exposure, giving lots of opportunity for the cats to remove themselves if they're uncomfortable. Don't force it!


Mutual feeding, treats, or even play on either side of the fence will help the cats make positive links between these great things and the other cat.

Feeding time, routines, and schedules are a great way to help your pet acclimate to their new surroundings, and doing those same things together can help them feel a part of the home. Your resident cat will learn that this new friend is just an addition to their regular life.

Eventually, the cats should seem eager to interact. Don't ever force this interaction. If your cats are not instant best friends, don’t panic! The important thing to remember is that cat introductions can actually take a considerable amount of time, and first impressions are almost never a good indicator of how they will get along (unless they instantly adored each other). It can take weeks to be completely comfortable, and sometimes up to months to snuggle or groom each other. There’s no way to know when things will happen, as every cat is different. But don’t give up!



Don't panic if there are some intermittent hisses or a swat or two. As long as it's not escalating into fights or prolonged stressful encounters, there's no reason to intervene. But that leads us to our next point....learning to recognize, prevent, or even intervene in the event of a fight.


Before allowing your cats to interact without a barrier or feeling very confident that they will get along, it's important to recognize the signs of danger.

Recognizing cat fight body language


NEVER allow cats to "fight it out". This will fracture any delicate trust that you have developed, and will make this introduction period take much longer. Remember, this process is not linear! Some days it will seem like they're ready to be best friends, and other days you'll wonder if they even remember each other at all. This is normal, don't lose heart. It's always better to go back to a previous stage than to push it too far. 

1. Puffed up: Most people are familiar with the bushy tail and poofy cat meaning agitation. What it actually is is something called "piloerection", meaning when the follicle stands on end. It's not always a bad thing, but means they're overstimulated. When viewed with a bunch of other warning signs, it can mean a fight is brewing.

2. Ears back

3 Forward body stance and tense muscles- this cat is getting ready to escalate towards the other cat.

4. Hard stare, unblinking eyes, often wide with large pupils

5. Close proximity

6. Ears back

7. This one is tricky- the body language in this picture indicates either preparation for "flight", or fight: about to lay on their side- this is NOT a submissive posture, but a tactical defensive position. Cats can kick extremely hard with their back legs, and are trying to remove a large side-facing target. 

Is it a fight or just a brief exchange of "words"?

If you hear or see some hissing and swatting, don't panic. We know it’s hard to not be protective, but sometimes some growling/vocalization/swatting, etc has to happen to help teach each other their boundaries. If it's a quick one off hiss or swat, that's just the cat letting the other cat know "I didn't like that".

If the interaction is progressing- one or both cats exhibiting prolonged growling, one or both going rigid, hard locked stares- break it up. Close the door to their home base and give the cats some time to cool down. 

Breaking up a fight

Fights can break out faster than you could imagine. One moment they could be fine, the next, they've decided they've been incredibly insulted and are now screaming a sound you've never heard before. It sounds easy to say, but try not to panic.

  1.  DO NOT REACH IN WITH BARE HANDS. You will get bitten or scratched.

  2.  Make a loud noise (clap your hands, stomp your foot, bang an object on a table). They may scatter. If they do, remove one of the cats to another room, being careful not to be scratched or bitten (use a blanket/towel if needed). If not, see below.

  3.  Grab a blanket or towel and throw over one or both of the cats.

  4. Get low to the ground and use your forearm (OVER the towel or blanket) to try to feel for where the two cats meet. Press down (over the towel or blanket) to create a barrier between the two cats.

  5. Grab ONE cat. Try to scoop the cat in the blanket so that they are cocooned, or if you can feel for it, grab their scruff THROUGH the blanket. DO NOT release the cat in the same room with the other cat.

  6. Remove the cat to another room to check for injuries. Do the same for the other cat.

  7. Seek vet care if needed. You most likely will not have to, but in the event of a serious bite or scratch, talk to your vet.

  8. Seek medical care if you are bitten. Cat bite wounds often require treatment.

  9. Breathe.

Cat fights often sound FAR worse than they are, and the biggest danger is breaking them up safely. Try to stay calm and remember that your stress can make it worse. Try to keep the interaction as short as possible and give lots of time for them to decompress.

If your cats do break into a fight, you may need to start the trust building exercises again from the beginning to reset the score. But don't worry, this doesn't mean they can never be friends. It may mean that their intro was a little rushed, and they need more time to get to know each other.

Cat intros


The ultimate goal is to get your new and existing cats to a place of mutual trust. While the cats don't need to live in complete peace and harmony just yet, they should feel comfortable enough around each other to begin to go about some semblance of a normal schedule. 

The most important boxes to tick before letting them run together on their own, especially at night:

  • When they see each other, they seem comfortable meeting gazes and going on their way

  • They seem more curious than fearful of each other

  • They can co-exist in the same room without being paranoid of the other's presence.

  • If there are any minor scuffles (an intermittent hiss or swat), they're brief and the cats choose to walk away or de-escalate on their own- if you have to intervene every time, they're not ready to be alone together!


Underdog alum Mouse (top) sharing a curious nose boop with her new brother after her successful transition period!



A week isn't that long in the grand scheme of things! While some cats are eager for a new little sibling, some cats have gotten really used to being an only child. Give it time and continue to try bonding exercises like mutual feedings, tandem play, etc. 


If things are going really poorly, reach out to us and we'll talk through your specific case with you. Underdog works hard to get as much info as possible, but sometimes a cat can surprise us and really prefer to be an only cat. Or your resident kitty could have limited cat socialization and would much rather be a single child. Talk with us and we'll determine if that's really the case. If they truly cannot be reconciled, Underdog will always take our pets back. But cats can be tricky, and we're committed to making it work.


A lot of play, especially at the beginning of new relationships can be a bit hard to tell what's normal, healthy play, and what's a true blue fight. Here's a video of Underdog alums Pumpkin and Spice playing that can be a bit challenging to tell:

Was that playing or fighting? The answer is actually both! Especially in young kittens, play is an important part of socialization and teaches them skills like bite inhibition (a fancy way of saying not biting hard enough to hurt). What you're seeing there is kittens engaging in normal play, one getting a little too rough, and the other one saying "Hey! I'm not gonna play with you anymore if you keep doing that!" All of that is normal and important! Don't interrupt this learning process! You want them to engage in this behavior young so that they have the skills when they're older.


We wish we could give you a standard answer, but the honest truth is that every single cat is different, and there is no way to know for sure how each cat will respond. We ask that, above all else, you meet the cat where they are and let them get comfortable in their own time.


No. Do not skip this process- no matter how well socialized cats can be, it's important to follow these steps. The good news is that if they truly are that great with new cats, it shouldn't take very long! But trust us, if you move too quickly, all the time you think you've saved will be wasted, as mending those broken bridges can take FAR longer.


In some behavioral cases, your new cat may be nervous around people, but great with cats. We will typically tell you that this cat gets confidence from being around other cats, and to let them meet sooner rather than later. Only if we direct you to do so, you can skip the process of getting them comfortable around you before letting them meet their new siblings. But still follow the cat introduction steps! We will have given more information about this at the time of adoption.


Reach out to Underdog for some relationship remedial steps you can take to work to rebuild trust. It's a much longer and more complicated process, but it's still fixable most of the time.


Cats, especially non-human-social cats, are usually nocturnal. Your new cat may need some help adjusting to this new life style. Try playing with them during the day, and keeping them from rooms where they can hide in dark places. Just like helping a human adjust after jet lag, you need to help reset their circadian rhythms. This will keep them from getting too rowdy at night and keeping you awake! Most cats naturally adjust over time, but some may need some help.

Any other questions? Don't hesitate to reach out to us. We're here for you and your pets, and can give more case specific advice if needed. Don't give up! We promise it's worth it!

Dog/Dog introductions

DO NOT attempt to introduce Underdog dogs to existing dogs without first receiving a behavioral consult from Underdog. We will help make your introduction plan, as it's very case-by-case specific. We'll take the guess work out


At this point, Underdog should have met your dog and done the initial off leash introduction to test the two dogs together. In that sense, this is much easier than all other introductions, as we can try to pinpoint any future tricky areas and give advise on how to navigate that. Follow the adoption plan provided to you, as well as the First 72 Hour Guide. When in doubt, reach out! We're happy to help.

Dog intros


As detailed in the First 72 Hour Guide, the name of the game is decompression. Dogs can be very stressy, so it's important to keep their first experiences positive and controlled. 

Assess your new dog's body language in the crate. Typically, the initial stress of the arrival to their new home has started to wear off and they're getting a little bit of a clue about how the routines work. Usually by this point, the stress hormones are slowly starting to dissipate, and they're most likely tired. They've been on high alert, and that takes a lot of energy. 


Underdog Zuko uses his crate as his happy place (notice the open door- he crated himself!)

Much like human children, a tired kid is a grumpy kid. You may see them start to act out a little more, pushing the boundaries. They may get more vocal or even a little destructive. Try to ignore this behavior and stay firm to your routines.

Or you may see them just completely conk out. They've decided they're safe and have a lot of sleep to catch up on. That's great, too.

Either way, it's important to respect where they are in this process. Look for key indicators that they're starting to feel more level. Their energy should feel less frenetic and more curious:

  • Calm watchfulness in the crate

  • Not overly prone to overstimulation

  • More relaxed body language, less tension and more loose wiggly bodies

It will be tempting to throw caution to the wind and start snuggling your new buddy on the couch or in bed. But remember, they've just barely got used to their crate and limited stimulus. Don't overwhelm them with too much of a good thing. 

If they're starting to get more level, you can start to do very controlled tandem walks with both dogs, but avoid letting them interact on leash. Make it a business trip; the goal is to potty and exercise, not socialize. Much like mutual feedings for cats, it's important to let the dogs know that this is just normal life now, another part of the routine. 

Continue to feed separately in the crate, avoid overstimulation, and stick to a solid routine. Avoid situations that set you up for failure. Instead, create a structured environment that helps dogs learn what to expect. Only once that is done can you think about dog/dog introductions.


While dogs are very much their own creature, sometimes it's helpful to compare them to human children, as some of the parallels are uncanny. One of our favorite comparisons is a child having a birthday party- at first it's great! So much to see, do, and it's all for them! We want to shower them with love and appreciation!  

After the initial wave of excitement, however, you can sometimes see kids start to shift. Maybe all the excitement has tired them out. Maybe they're massively overstimulated by all the new sights, sounds, colors, and opportunities.

Then comes the meltdown.

It's all too much, and their body reacts the way it knows how to shut it all down- a tantrum. Now you have a sobbing 2 year old clutching a balloon, and you're wondering what went wrong- this was supposed to be fun! Why are they acting out?

It's just too much birthday. Too much of a good thing!

too much birthday.jpg

While humans and dogs are completely different, this process is caused by the same human element.

Everyone has seen the cute videos of the dogs being brought home from the shelter and being given a million new toys, unfettered access to the bed and couch, etc. And it's lovely! We want to show the dog how much we love them, and how safe they are. It comes from a great, sweet, place and is the best of humanity. But that's just it- it's a human thing, not a dog thing. And we have to be careful not to project our desires on to our new dogs. 

But when you take a dog from a stressful situation and shower them with a bunch of new stimuli without teaching them how to safely interact with their environments, too much birthday can happen. Remember, even good things can be overwhelming, and when overwhelmed, dogs do what they know how to do: they can bark uncontrollably, nip, bite, or even get in dog fights with a dog they seemed to get along with just fine before.

For this reason, this is why we don't recommend allowing your new dog to try to play with your existing dog until the routine has been established and they've grown comfortable in their new setting. "Too much birthday" can cause your overstimulated new dog to react out of character in ways that we as humans may not fully anticipate. 

Also, much like human children, it's important not to neglect the other sibling just because the other one has something new and exciting going. Make sure you're running the same routines with your resident dog to help get them in the mindset to set a good example for the new canine companion.

Once you feel your new dog has gotten the hang of the routine, doesn't get overly excited or stimulated by seeing the other dog, and is comfortable in the home, we can work to introduce them to life with their new dog sibling!


Ok, you've been patient and allowed them time to decompress. Time to learn the ins and outs of their new home, and time to acclimate to daily life. Now are they ready to interact fully with their new dog sibling?

Yes (and no). You're so close!

Before letting slip the dogs of play, do a quick check of the area in which you'll be allowing them to interact. The best option would be a private, fully fenced yard. But if you have a dog area at your apartment complex, or just a large enough living room, that could work too. We'll give you tips to prep each space.

Your big backyard

If you're fortunate enough to have a fenced yard, that's a great place to let your dogs fully interact and play. The other options you have would be to rent one off of SniffSpot, borrow a yard from a friend, or find a private enclosed (and fully fenced) area where dogs are allowed off leash. Having enough space is important! Remember a few things when using a yard:

  • No toys or food- don't give them anything they might compete for.

  • Keep the space as neutral as possible. Avoid items of "high value".

  • Fully fenced- walk the perimeter of the fence and make sure there's no where a scared dog could slip out or jump over. This happens far more often than you could imagine.

  • Safety- if you have any safety hazards like a pool or any holes, try to block them off.

  • Close off access to the house.

This yard is ideal:

  1. A tall, well maintained fence without gaps or holes​

  2. A clean, neutral yard with no toys or high value objects

  3. Clear lines of sight to monitor dogs

  4. Lots of space for getting away from each other if needed

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DO NOT use a dog park! There are far too many uncontrollable variables, and too much risk! 

Indoor Intros

Be cautious when doing indoor space introductions. The more confined quarters are harder to navigate, and can result in some collateral damage. It's also a much more precious space to your previous dog who may feel like their space is being invaded, and can result in some guarding behavior. It's much better to try to use an outdoor neutral space.


Helper dog Zuko (left) teaching Klahaya the ropes to indoor interaction.

  • No toys or food- don't give them anything they might compete for.

  • Keep the space as neutral as possible. Avoid items of "high value".

  • Close doors to other areas to prevent them running past to harder to control areas

  • Move anything that could be broken by roughhousing

  • Be aware that your resident dog has MUCH more attachment to the area and can create an imbalance in which your first dog feels the need to guard their space. This can cause fights or general behavioral snafus. This is not the best space for dog intros.

Tools to have on hand:

pet corrector_edited.png
collar and leash.jpg
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Flat collars and clip leashes

Spray bottle

Pet corrector

Dogs should have a well fitting collar and a clip leash dragging for easy control and separation if needed

An option to help interrupt unwanted "nuisance" behavior

Loud compressed air for more serious scuffles, can distract and prevent altercations

air horn_edited.png

Air horn

Used for the same reason as the pet corrector, though should be saved for breaking up serious fights; can cause hearing damage


Assuming the dogs seem to be having positive interactions thus far, and you've set the stage for a neutral introduction, you may proceed to let the good times roll! A couple tips for success:

  • Make sure both dogs are wearing well-fitting collars and clip leashes. That way, if a fight breaks out, they won't slip out if you need to pull them apart.

  • NO toys or treats- avoid things your dogs may compete over. 

  • Drop the leash: it may seem counter intuitive, but on leash interactions often cause more incidents than off leash. Using a "drag leash" is best- a plain flat leash clipped to a secure collar that you can step on if you need to get ahold of them

  • DO NOT use toys- the trust is not strong enough yet and you don't have enough info about the dogs to know how they'll react with a "high value" object thrown into the mix. Their focus should be on the other dog and you alone.

  • Stay vigilant: even if it seems to be going well, continue to monitor for signs that the dogs are happy and enjoying the interactions

  • Stress, not distress: Remember-  a little stress is okay, that's how we learn and grow. Distress is not okay, and needs intervention.


Image courtesy of DPFL/Josh Feeney/Safe Humane Chicago- Demonstrating a drag leash and happy, loose body language


Dog fights are serious and often dangerous for both the dogs and people. While it's rare to have a true blue dog fight, it's important to know what to do as a dog owner. It may not happen with your new or previous dog, but it could happen at a park, on a walk, etc, so it's important to know how to react to protect the dogs and yourself. No one explains this better than a group called Dogs Playing For Life, a group that travels to shelters to teach behavioral rehabilitation through play groups.

From the Dogs Playing For Life Manual:

dog fight.jpg

Please note: this image may not be a fight. You need to know the full context for certain actions to determine whether it's a full fight or play behavior.

If a fight breaks out, keep your cool and focus on safety for the dogs and people involved. 
• Always use startling tools first: pet corrector, air horn. If
they have startled apart from each other, calmly take them by their
attached leash or collar and move them apart.
• If startling fails, be quiet and calm. No yelling. If the air horn didn’t
work, neither will screaming at them. Yelling may escalate the
• Do not hit the dogs. Causing them pain will not end a fight, but it
may cause an escalation in aggression to dogs and/or people.
• Use any object to get between the dogs: trash can, chair, etc.
• If the dogs are still engaged, grab the dogs by the hind ends or their leashes, before you grab their collars (dogs may redirect onto you if touched while they are in a heightened state of fear or arousal).
• If the dogs are tightly engaged or holding on to each other, DO NOT PULL DOGS APART. Pulling can cause far more
serious injuries – such as tearing – than the bite itself.
• Immobilize the dog who is holding on and “feed the bite” by
controlling the back of their head and pushing into the other dog.
Push in, don’t pull apart.
• Be mindful of defensive mouths and remove your hands if necessary to avoid handler injury.
• Only pull dogs apart once they have let go of each other.
• Do not let go of the dogs. Remove the offender from the yard.

Predicting a fight

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It takes a seasoned dog behavior reader to anticipate when a fight will pop off, and even then, they can miss subtle signs or misinterpret perfectly fine behavior. Please read this segment from the Dogs Playing For Life manual for more information.

Dogs Playing For Life

We're sure you've noticed how much we reference Dogs Playing For Life- that's because they see first hand more dog social behavior than anyone else. This is a fantastic organization that travels the country to provide play group training to shelters to encourage them to use group play as a stress relief and socialization tool. But that requires understanding the risk and behaviors that can lead to fights among dogs when we don't know the full histories.

We recommend visiting their site and reading their group play manual if group play is something you're interested in, or learning more about warning signs of dog fights.

Please note- Underdog often requires certain dogs not be involved in group social settings such as dog parks, as there are many people who don't know their dogs triggers. Please consult your adoption aggreements to see if we feel your dog is a good fit for group social engagements.



No. That was an initial assessment to see if they could be a good fit. It's no guarantee that they're going to be best friends right away. Dogs have good days and bad days just like people, and different stressors can cause different reactions.


Yes! We'd love to help your dogs get settled. We're here for you. You can send us videos of specific behavior if you've got particular questions, or if you're generally just unsure, we're happy to come check them out in home to give you some tips and tricks.


Dogs give each other corrections that to humans can look intense. But that's just that dog setting a firm boundary, which is okay.


Give it time. You may have heard this before, but it can take 3 months on average (so sometimes longer) for a new dog to feel like a part of the family. They need time to feel comfortable and safe before you'll start to see more happy body language.


NO. You do not know your new dog well enough to know what their triggers may be. This is a recipe for a lost dog or a dog fight. Build the routine, build the trust, and then you may use your judgement (unless your adoption contract states otherwise). Some dogs just aren't dog park dogs and that's okay. Don't force them to do the things you want them to do. Instead, meet them where they are.


This is a loaded question, because everyone has different definitions of behavior testing. We do not purposefully expose animals to stressors, cats, or children. We do make assessments and decisions based off of the evidence we see, but "testing" animals often gives completely false data that may provide a false sense of security, or conversely, too harsh of a judgment. We will instead offer that advice that that animal may not be a good fit for certain settings. We rely on context and experience to make judgments about good behavioral fits, and work to get the animal the core fundamentals that will set them up for success in new settings. 


Dogs often suppress a lot of behavior at first while they're still learning the ropes. Don't be surprised once they get comfortable to see them start to push boundaries. They're experimenting with what you'll let them get away with! Stay strong, stick to the routine, and ask for help if needed.


As much as we pride ourselves on getting to know our animals, they can behave in unexpected ways in new settings. We don't have a crystal ball, but we do have lots of experience and know how. We can only make informed guesses based off the behavior we see exhibited while with us, and any data we may get from their original source.


While we're glad it worked out for you, we had reason to believe that that may be risky or dangerous. We have to do our due diligence and warn against things that in our experience and expertise may be unsafe. It also doesn't mean that they're always going to be fine with that situation again in the future. Please be cautious and heed warnings we may give you.


Yes! Please do, we love love love updates and pictures of dogs with their new friends! And we're always happy to talk through behaviors, make recommendations, and generally love on your pup with you.

Cat/Dog introductions

As much as we try to make assessments, there is no behavior test that can tell you 100% without a shadow of doubt that a dog will be safe around a cat. We will never promise a dog is safe around cats; all we can do is tell you what we know of their history (if they've lived with cats before) and what we have observed ourselves. Any shelter or organization that tells you they have "cat tested" a dog is not preparing you and your new dog for success. 


It's important to understand that animals are extremely variable creatures. We cannot (and will not) ever 100% guarantee an animal's behavior in the future because there are an infinite number of factors that can change what they decide to do. From stressful changes, to not vibing with a particular cat, to just having a bad day, dogs are as emotionally volatile as people.

For this reason, you must be constantly monitoring your new dog around your cat to watch for signs that trouble could be brewing. Dog to Cat introductions are very dangerous, as it doesn't take much from a dog to hurt a cat. Be cautious, and when in doubt, back up and take things slow!

Cat/Dog Introductions

Things to watch for:

Before diving into the introductions, here are key warning signs that you need to be able to recognize and avoid:

Hard staring: Very intense eye contact that will be uninterrupted by blinking or movement, possibly partnered with stiff or low body language. This could indicate a "prey drive" that can result in a dog seriously hurting or even killing a small animal due to no other reason than hunting instinct. In some cases, it could just be extreme interest that is not dangerous, but it is difficult to distinguish.


hard eye.jfif
hard stare.jfif

Examples of "hard stares", possible prey drive. Note the intensity and rigidity of the body.

prey drive.webp

Stalking: While there are a few dogs who play this way, this is usually a sign of danger, especially with a new cat. The low body language, tense muscles, and unblinking hard stare combo are massive red flags. This may be prey drive, an instinctual behavior that can result in serious injury to a small animal. Remove the dog or cat IMMEDIATELY.

Chasing: It is NEVER okay for a dog to chase a cat! Even if it is "playful", this is stressful and dangerous for the cat. If a dog starts to take off after a cat, remove the dog IMMEDIATELY.

Example of possible stalking/"hunting" behavior. Could be innocuous, but could be prey driven.

Freezing/stiffening: Often seen when the cat or other animal approaches the dog or something of value to the dog. This can be followed by lunging or snapping. It can happen in a snap second, so be vigilant for this behavior and be prepared to intercede. You should not be in a situation where this may occur unless the dog has undiscovered behavior issues down the line; otherwise, all introduction situations should be designed to prevent such an event.

Example of stiff body language/warning sign of a fight/bite in both of these dogs: close proximity, hard stare, stiff bodies, avoidant gaze, etc.

This should be broken up immediately.


THESE SITUATIONS ARE DANGEROUS FOR THE CAT. Compared to a dog, cats are fragile! One bite could be disastrous for a cat, so we must use caution at all times. These are just some of the basic danger signs to watch for. When in doubt, please consult an in home trainer to help you with introductions.

In some cases, dogs that are believed to be safe with cats might just not be a good fit. Remember, we will always take our animals back. We'd rather be overly cautious than allow your kitty to get hurt. 


If the cat in this situation is the new comer to the home, please be sure to allow them to acclimate to the new home as described in our new cat guide.

If you try to rush this process, the trust and bond building will take infinitely longer, so be sure to take it slow!

If the dog is the new kid in your home, please follow our first 72 hour guide (coming soon) to help the dog decompress before adding this relationship to the mix.

It's important to set your new family members up for success. It's infinitely harder to repair a rushed, broken relationship than it is to go slow and build the trust from the ground up.

If you've successfully completed the steps in these guides, you're ready to start introductions!

What you'll need:

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A baby gate: helps control the space and provide barriers

An appropriately sized exercise pen is a very useful tool for controlling space or corraling an eager dog

A towel or blanket can be used to throw over fighting animals to safely remove them without you getting hurt

If your dog has a good relationship with a muzzle, this is a great peace of mind tool.

Set the stage

Get your dog ready for meeting their new cat sibling! Put on their leash or harness, and if they're muzzle conditioned, this is a great way to give you peace of mind.*

Set up the barriers, like baby gates or exercise pen (also sometimes called a flex fence). You want a space that you can control. We recommend setting the baby gate up not directly on the room the cat has been staying in, but maybe in a hallway a few feet away from that room. Close any other doors so that the cat just has their home base and a little bit of space outside of it, if possible. Otherwise, use the exercise pen to create a little bubble outside of that space. This is to prevent the cat from feeling like their home base is no longer safe, and give them the option to run back to it if things get overwhelming.

Remove any high value items such as treats, toys, bones, beds, etc. You want there to be as few factors to control as possible.

Once the room is ready...sit down and relax. Your dog will most likely be STOKED- you put on their leash and moved stuff around the house! They may think it's walkies time, or there's something weird happening. It's all pretty exciting. Give the dog (and yourself) a second to breathe and set the right emotional energy for the next interaction.


Image courtesy of Top Dog Tips

Top: 2 dogs off leash is a lot for one cat, but this cat seems okay with the arrangement. The amount of space they have to move away is great, and the height security of the gate is well judged.


Crating your dog is a great way to convey to your cat that it's their turn to safely investigate.


Once you and your dog feel settled and calm, you can open the door and let the kitty walk out in their own time. Do NOT force the cat out, or force your dog to walk up to the gate. Instead, try to model calm behavior. Sit on the ground and hang on to the leash at all times. Watch for any of the previously mentioned warning signs. 

Stay engaged! It can take just seconds for the tone to shift. Being engaged, watchful, and anticipatory is key to keeping everyone safe. 

*While Underdog loves using muzzles to ensure safety, using a muzzle without properly conditioning the dog to it can be stressful and damaging for them. If you feel you'd like to use a muzzle for introductions, either work with a trainer or read up on muzzle conditioning so that your dog doesn't make a stressful affiliation with the new cat and the muzzle.

Your primary focus should be on your dog. Watch for signs that they're not listening to you anymore; they should be responding to input from you so that you're still in control of their stimulus levels. If your dog is just going off the rails, not listening to you, end the session. The goal is get to a point where your dog is reactive to your directions even with the excitement of a new friend.

If the kitty seems curious and calm, and your dog is responsive to your input, you can walk your dog up closer to the gate. Allow them to smell each other. Then walk them back and reaffirm that your dog is still listening to you.

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Keep the sessions short and sweet; you want all of them to end on a positive note, and reward everyone for positive interactions after the fact. (Avoid treats during the session- you want to avoid adding anything high value or distracting during the intros that could lead to issues like fighting over dropped treats, enticing the cat too close, etc). 

If your cat starts to try to break out, consider a higher fence. The key is to control the space and the amount of exposure they have to each other until you feel confident they can coexist.

This is a good sign from the cat that they're not too scared by the dog- sitting close and engaging is good! This is a good later stage sign of progress. While we recommend keeping the dog on leash, it's good to see relaxed and curious body language.

STAGE THREE: LET THE GOOD TIMES ROLL....slowly and over time

Don't be worried if they're not snuggly best friends yet- it takes time! Instead, look for peaceful coexistence- even just hanging out in the same room is great! But remember that it can take a while for a dog to truly understand that the cat is a new sibling, and not just a fun new interactive toy. Keep watching, stay alert, and be an advocate for your cat's comfort and safety.

If after ages of trying these steps, you still feel your dog is too intense, we recommend working with a trainer to create a plan that suits your dog's specific needs. If you feel that it's just not a good fit and you're concerned for the safety of your animals, we understand that sometimes these things just aren't quite right. We will always take our animals back, and want you to feel safe and confident about the animals in your home.

If your cat still seems fearful even after months of adjustment and trying various strategies, this might just be too stressful for them. It's important to consider their happiness too- especially if they were there first!

It's so important to listen to what our pets need, and not force them to do something just because we want it.

Part of owing cats and dogs together is being realistic about their needs; they are two wildly different species, and at the end of the day....they're animals. We have to do what's right by them as individuals, not just as "our pets". 

With time and effort, if it works, it just works. And if it doesn't, that's okay too. we're here to talk you through the next steps and make plans to do what's best for everyone.


Underdog Alum Obie with her big dog foster brother, Zuko

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