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From First Date to After the Honeymoon: Adopting a Dog Into a Multi-Dog Household

Missed our recent webinar on multi-dog households with Patricia McConnell, PhD, CAAB? No worries—the rockstar canine behaviorist and trainer shares sage advice from the webinar here.

As you can imagine, there is so much to cover here! I’ll summarize some of the most important points in this blog, but please listen to the webinar to look at this topic in more depth. You can find additional resources on my website.

Some aspects of dog-dog introductions are universally agreed upon, such as giving the dogs as much freedom as is safe, and using a large, neutral area if at all possible. Outdoors is always better than indoors, unless the only outdoor option is a small, confined space. Just remember that the less pressure on the dogs the better, and that “pressure” can be applied by confining dogs to small spaces, looming owners or dogs unable to move freely. Most importantly, no matter what the setting, do all you can to keep the initial introductory sniffing brief. Let the dogs interact briefly, and then call them away. Move around the space yourself, encouraging the dogs to explore the environment together, perhaps providing themselves information about one another through scent marking. Avoid long, up-close-and-personal sniffing sessions that often lead to tension and bad beginnings. On-leash or off-leash depends on a variety of factors, but do what you can to avoid tight leashes that add tension.

Some shelters and rescue groups mandate that potential adopters bring in the resident dogs for a “meet and greet” at the shelter itself. There are a host of costs and benefits to this practice. These include a chance for the host organization to evaluate the skills of the potential adopters and the condition of their current dog, as well as a chance for the first introduction to go badly because the dogs were forced upon one another. I would argue that resident dogs should only be brought for meetings if “best practices” can be followed, and the dogs’ first minutes together are structured in such a way as to encourage a good, long-term relationship. In addition, we need to guard against assuming that first meetings are always predictive of how the dogs will get along in the home. First greetings are often not predictive of how the dogs will get along in the home, and suggesting otherwise only compromises the credibility of the shelter or rescue group.

Most importantly, expectations should be realistic about how long it takes dogs to settle into a new environment. All new dogs are in a state of confusion about where they’ve been and where they are going. New owners need to help dogs get their paws on the ground as soon as they can, but without overwhelming a dog who is unsure of himself. Good management is often the key here: Give dogs lots of time by themselves at first, letting both the new and resident dogs have rest periods and special time by themselves with their new owners. 

Many problems between dogs can be prevented or managed by teaching dogs that they get what they want by being patient and polite. Rather than following the ancient (and sometimes destructive) advice about supporting the dog who they think should be alpha, owners should teach dogs that they get treats, toys and attention by being polite, not by being pushy.

One of the most common mistakes I’ve seen from owners of multi-dog households is unrealistic expectations. New dogs can’t settle into a new household in a week or so—it can take up to a year for a new dog to settle into a new routine. Expectations can also set owners up for a lot of soul searching and “buyer’s remorse.” Wondering “Oh no, what have I done!” is a common reaction to the slightest misbehavior of a new dog, even among experienced professionals. The more we can help all new owners by being there for them when they need someone to talk to, the more dogs will stay in homes and not be returned to shelters.

Regrettably, sometimes things just don’t work out. Perhaps the two dogs simply despise each other, and no amount of training or conditioning is going to change it. Sometimes one dog brings out the worst in another, and the combination is too much for even the most dedicated owner to handle. In that case, we need to let owners know that they have a backup plan available to them. Service providers must accept dogs back without causing adopters to feel guilty. “Satisfaction guaranteed” lets responsible adopters know that they can count on the shelter or rescue group to be there for them if they need help. People are more likely to adopt if they know that they are not going through this without support from professionals.

None of us can accurately predict how any group of dogs is going to get along, but we can do a lot to increase the odds of a successful transition from a “one-dog house” to “multi-dog household.” Shelter staff and rescue organizations can and do play a huge role in helping to integrate dogs together into a happy family—thank you for those efforts! Picture me wagging from the shoulders back…


Patricia B McConnell, PhD, CAAB, is a zoologist, animal behaviorist, teacher, speaker and author who has been working with people and dogs for over 24 years. Her work and speaking schedule can be found at, and her blog at Currently she is working on a memoir.


Related links:
Patricia McConnell, PhD
“The 3 Most Important Things to Say to Adopters About Their New Dog”
Webinar with Dr. Patricia McConnell: “Multi-Dog Households”
Webinar with Dr. Patricia McConnell: “Increasing the Odds of a Successful Adoption”

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Wonderful advice and I just had to tell you that I LOVE this picture of the two Great Pyrenees. 


Great article.

What about when the introduction and integration goes great, but the dogs together then develop pack aggression towards outsider dogs? 

That is our situation... 2 years ago, we bought a one year old female pup as a playmate for our then 7 month old bored female pup. We lived in a one bedroom apartment in a beach suburb, but were in the process of buying a house in an outer suburb, and the purchase of the new pup was conditioned that the house deal would go through, otherwise we could return her to the foster carer. Both dogs responded very positively (to say it mildly, in regard to the pup we had - she was over the moon of happiness about her new big sister!). 

Both pups, when we found them, were described as very dog friendly, kid friendly, well socialised et.c. Our first pup grew up in a big pack in a village and interacted with many different dogs, kids, cats and other animals from she was a baby. We don't know much about the newer dog's background, but she lived with 6 other dogs in the foster carer's apartment and was very sweet and polite (still is). She had been surrendered to a pound when she was 6 months old where she only spent a week or two before she was adopted, then was giving over to the foster carer a few months later for for family emergency reasons.

The dog-agression problems towards stranger dogs started about 3-4 months after we moved to the house, which we did a few months after getting the second dog. 

There is a huge contrast in the "dog culture" of the beach suburb we lived in before (vibrant, lots of local trade, residential apartments, some houses, lots of parks) VS the typical outer suburb (houses with secure yards, bush, purely residential) we live in now.

Dogs in the beach suburb were (are) plentiful in the streets - they are everywhere you look, and generally friendly, together with families and kids, and very well behaved - most of them just following their owner or family off leash in the streets (although that's illegal, no body seems to care because there are rarely any issues and the dogs are generally polite). Just like most dogs there, our dogs got plenty of daily walks while we lived there partly because they were big pups and we didn't have a yard or outdoor area other than a balcony, and partly because we lived surrounded by pleasant outdoor spaces like nice parks (mostly off leash), the beach and outdoor cafes welcoming to dogs so, it is was very easy to take the dogs when strolling down for a coffee break.

Dogs are plentiful where we live now too, but most are invisible. Most or all live in secure yards and we can hear them and can by sound tell that there are many multi-dog households in the neighbourhood, but we rarely see dogs in the street. When we do meet dogs on walks, most don't walk properly on the leash (pulling, zigzagging, erratic) which provokes particulary our newer dog, and many dogs we've encountered on walks here were extremely aggressive and erratic. Most dogs are being walked on leash, but if off leash then their owner tends to turn pale when he/she sees another dog and hurry over to get the leash on their dog lest a catastrophe ensures. That's pretty much how our dogs behave now too, and we never have them off leash anymore outside our property. They get one daily walk plus one of them get a daily jog in the bush with me plus sometimes some extra walkies or car drives just for the fun of it. They are now big dogs and very strong, so when we see an unfamiliar dog then I get them to sit down out in the side until the dog passes... They are not so likely to "freak out" when they are not in motion, so that is easier to manage. They also get rewarded for good behaviour and that way we don't have many totally freak out incidents, but every dog we encounter except for their few doggy friends, is an Issue to be handled correctly or else... before I learned this, I have been dragged over the ground dangling after my two monster-like dogs like a sled. 


The newest dog is the one who started to become aggressive first, then gradually our first dog joined in (she is no angel), and she is still the most aggressive. She is in all other situations super sweet, loving and extremely polite. She has attacked other dogs 3 times. One of the time can be excused - she defended the second dog from repeated, unprovoked attacks from a dog in an offleash park (which I was trying to get off my dog while the owner didn't do anything). The other 2 occasions were unprovoked (except for barking) attacks on little white fluffies where she accidentially got free (broke a leash; pushed out of a screen door that was not properly locked - such accidents can't happen anymore now when we're aware of the risks). In one of the cases she managed to grab the fluffy in her mouth with lots of angry growling, before the panicked owner managed to snatch his dog back. In none of the cases did any dog actually get physically injured although our dog looked like an insane monster gone totally bananas. This is the same dog that, when we lived in the beach suburb, daily played happily in the off leash park with our other dog and whatever dogs we met there and which was very tolerant to aggressive little dogs we met on leash. And as I said, other other dog is now dog-aggressive too, and worse if she does get into a dog fight because she doesn't have the same strong bite inhibition.

Does multi-dog householding risk to foster dog agression, have we been unlucky, or have we done it wrong?      


My sympathies, and I doubt very much that you have done anything wrong at all. Your comparison of the two neighborhoods is a classic reminder how leashed dogs become more and more uncomfortable around others. The attack at the dog park, however, probably also had an important effect on her, along with simply getting older which often correlates with less and less patience around other dogs. Having two dogs probably had little effect on your females problematic behavior, so I wouldn't let it stop anyone else from adopting a second dog. I love that you are managing the situation by reinforcing the dogs for polite, calm behavior. You might want to bring in a professional as a coach, just to see if you can do even more. All best and good luck!



I am not an expert at all, but have been a dog owner for many years. Our current dog is a 95 pound black lab who is a rescue. We have had her for almost four years. I think the problem you are experiencing has more to do with the change in environment than having multiple dogs. Our dog acts very differently when she is on a leash and when she approaches another dog on a leash. She is much more territorial and "defensive". Same goes for being in a fenced yard and barking at everyone who dares go past "her territory". When she is off leash and meets another dog off leash, she is very friendly. The change in your neighborhood has gone from being family/dog centered around community to one of clearly marked territories and I think your dogs are simply trying to defend theirs. A hard issue to train, but maybe a trainer in your area can help.

i don't have an answer for you, but perhaps someone else will be able to post a comment that will help your situation.


Anna, it's not so much about having two dogs, or a multi-dog household, but the personality of the two dogs and their experiences. It does sound like the attacks at the dog park had a significant effect on your dog's behavior. And please don't feel like it's all your fault! Problems happen to the best of us, and I am so glad you are managing it well by reinforcing your dogs for calm and polite behavior. If I were you I'd bring in a progressive trainer to help you move even farther along. Good luck!


I think it's interesting the point about how long it takes a dog to adjust. I have always had a mulit dog household of rescue dogs. One in particular really didn't let her true colors show for a year. I had never had a dogs who's personality really evolved so much from a sweet willing to please dog to a seemingly stubborn selfcentered (or whatever the non anthropomorphic term is). And of course feeling guilty and embarrassed and committed, I'm stuck with a horrible dog (I'm not sure if it's just a personality conflict or that she's just a total brat). 

I'm interested in how to cope with this, loving a dog that just doesn't seem to give a s**t about me and what I'm doing unless food is involved, is really hard to do. I try my best but I don't want to pass off a problem dog to someone else where she would just get bounced around continually. That isn't fair to her. 


Stephanie: This is tricky to answer without having met the dog. However, one key with food obsessed dogs is to vary the reinforcement schedule. In other words, don't give them a treat every time once you have the behavior started, thus teaching them to keep trying in order to get what they want.  I also like to vary the reinforcement early on too, whether it's asking a dog to sit before opening the door to the out of doors or asking for a quick Stay and then releasing and giving a belly rub. The key is to look at your dog's day and note all the things that he seems to enjoy doing, and use those as reinforcement as much as food.

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