Whether you’re bringing home a new puppy to your pack of dogs or merging you and your new partner’s dog and cat households, pet introductions can be tricky! Here’s how to help them go more smoothly.

Adding a new pet to your household is always an exciting time, but it can be a little more complex when you already have pets at home who are set in their ways. They’re about to have their world rocked by a new animal arriving to compete for toys, food, and your affection. Even typically friendly pets might feel a little on edge in a situation like that!

The best case scenario is that your pets will become fast friends—and some chill pets might make the intros easy with a casual sniff leading right into a game of tug-of-war. However, most pets will require a little more moderation from you to make their introductions easy!

Introductions are typically the easiest among young pets, even across species. Puppies and kittens who are raised together are the most likely to be well-socialized and have an easy relationship into adulthood. You’re not out of luck if you’re working with adult animals, though. Even if you have an old dog who hates learning new tricks and you’re moving in with your partner and their persnickety cat, there is still hope!

Here are the best, science-based tips from animal trainers and behaviorists to help take your pets from strangers to happy housemates:

#1. Nail Their Basic Training

Before you consider bringing another animal into your space, you should make sure that your current pet’s training is as strong as can be.

This is especially important if you are introducing animals with a high prey drive (a common dog behavior in many terriers and hunting dogs) or who aren’t great at reading social cues about when other animals want to play. Many cats don’t get along with overly-enthusiastic pups, and cat and dog introductions can lead to nasty scratches if a dog doesn’t give the cat enough space!

Train your dog to listen to “leave it” or a similar command to redirect their attention when necessary. This will help to break them away from chasing or roughhousing with other animals before things get heated! Even better, give them a space where they know to settle on cue like a mat, bed, or crate, giving them time to cool off before going back to their new friend.

If your dog’s obedience skills are a little rusty, consider working with a dog trainer with plenty of hands-on experience to establish a solid training program for your pooch!

#2. Start by Keeping Them Separated

As tempting as it might be to plop a cute puppy or kitten down on the floor and see how your pets react, that can be a risky move for all pets involved. It’s best to keep any pets you’re introducing in separate areas of the house as they get used to the smells and sounds of another animal in the house.

Use closed doors to give them each separate zones of the home. Most cats can be content in a single room for this trial period as long as they have all the essentials (food, water, and litter box) in there. It’s best to give the pets who were there first as much room to roam as possible so they don’t feel like the new animal is encroaching on their territory.

They’ll probably be interested in whoever’s on the other side of the door and doing lots of sniffing! That’s a good sign as they get acclimated to each other.

#3. Introduce Them to Each Other’s Scents

Animals get to know each other through smell, and getting them comfortable with a new animal’s scent in their home can be hugely helpful in laying the groundwork for a successful introduction.

Let each pet cuddle up on soft objects like a blanket, towel, or cushion, and then swap them after a few days. Each animal will get used to the other’s scent and learn to not view it as a threat as they get cuddly with the same cozy blanket. You may repeat this process multiple times, adding more scent-marked fabrics to keep the scent fresh and establish their presence in other areas of the house.

This process can be done in one home while the animals are still separated, or can be done between homes for an even more gradual introduction.

#4. Set up Safe Zones for Your Cat

If a cat is part of your introductions, it’s important for them to have a safe, dog-free space for them to retreat to whenever they want a little space. This could be a tall cat tree where they can survey the space (and dogs) below or a closet or cubby that has a cat door that’ll keep the big dogs out!

Try to get them comfortable in this space before introductions start so they know exactly where to go if a pooch has a little more enthusiasm for wrestling than they do.

#5. Give Everyone a Workout Before Introductions

Introducing two pets who are feeling a little stir-crazy is a recipe for disaster! It’s best for pets to be as mellow as possible before introductions. Take your dogs (and leash-friendly cats) for an extra long walk or give them some good dog or cat enrichment activities to burn some energy. This will help them be more relaxed when they’re greeting their new roommate.

#6. Start Introductions at Mealtime

It may seem counterintuitive at first, but dinnertime is a great time to begin your pets’ introductions! There’s a reason so many human first dates happen over dinner—eating together makes us feel safe, and the same applies to your pet.

Start this process on opposite sides of a closed door. Keep any dogs on a leash for now to prevent lunging at the door and set up good habits for later in the process! (You may also consider using a leash for your cat if they’re leash trained or prone to being aggressive, but cats are typically more likely to run from stressful situations.)

Serve up each pet’s meal as usual, and let them chow down while taking in the sounds and smells of their new housemate doing the same on the other side of the door. Keep repeating this process until it becomes a normal part of the routine and your pets begin to associate the other animal’s presence with tasty food! This may take a couple of weeks, but there’s no need to rush.

Once they’re totally comfortable with this routine, start replacing the closed door with a dog gate (the old baby gate your mom has in storage will work just fine). Seeing each other will add a new variable to this process, and they may be eager to approach the gate for a good sniff! That’s okay, but make sure to keep a good handle on their leashes to keep their interactions controlled. Continue feeding like this until this becomes routine again!

The next step is (drumroll please!) taking down the gate and letting them eat side by side with no barrier. This is when good leash control is especially important—you want to be ready to jump in and quickly redirect any negative interaction between your pets. Food-motivated animals may still be mostly focused on the food, but your pets will now have an opportunity to get close, sniff, and even play if they choose to!

Once you’re totally confident that they can interact peacefully, you can take off their leashes and give them a little space. You should still continue to supervise any interactions for a while, but congratulations—you’ve successfully introduced your pets!

#7. Continue to Use Good Habits

Your pets comfortably occupying a space together is a huge milestone, but it isn’t the end of the road! Animal behavior is complicated, and you might discover surprising points of friction as your pets get to know each other.

If your pets show any tendency toward resource guarding, do your best to give them their own resources. They should each have their own toys, and you can make adjustments to keep food separate too. Consider staggering their feeding schedules, putting your cats’ food bowls on elevated surfaces, or using microchip-activated personal feeders to prevent your pets from stealing each other’s food and causing conflict.

You should also continue their education by using positive reinforcement whenever they have good interactions with their new housemate! Depending on how stand-offish they are, you can start small, doling out treats when they simply look at the other animal to create positive associations. As they get friendlier, you can provide praise or treats when they cuddle up next to each other or play comfortably to encourage their growing bond!

Introducing pets can be intimidating, but with patience, positive reinforcement, and understanding, most pets can become comfortable roommates. If you’re lucky, you might just have two new best friends!