When choosing a new dog, try to match your dog's personality and temperament, and most importantly, play style as well as your family's lifestyle. If your resident dog is a lap dog, he/she might not welcome an active terrier or herding breed. For example, a couch potato type dog is not the best match for a very active dog or household.
- All dogs should have basic manners, for harmony as much as safety, but this will be more important when bringing in a second dog. If your dog needs a refresher course, do that first. Training is also a good way to bond with your new dog. A great relationship builder is working with both dogs to teach manners together.
- If your dog has any behavioral problems, you should resolve those before bringing in a second dog. If your dog isn't completely housetrained or barks all the time, you'll soon have two dogs with that problem. There are a few exceptions, such as a dog suffering from separation anxiety from being alone for the first time in its life. This dog may actually do better if you bring in a second dog.
- Give both dogs some exercise (separately) before the introduction, so that they will be a bit tired and more relaxed.
- Introduce the dogs on neutral territory – in a park, for example – not in your home. This is very important. If you bring the new dog directly into your home, your dog may feel that his or her territory is threatened, and may react defensively or aggressively. Take them for a walk, having them walk side by side, not one in front of the other.
- Keep both dogs on a leash, even if they are in an enclosed space, to give you control if one becomes aggressive. (You hold the resident dog's leash – have a friend hold the other.)
Keep a positive attitude and speak calmly. Avoid high-pitched, rapid-fire "reassuring" words and anxious petting, which we construe as calming, but dogs hear – rightly so - as anxiety-ridden.
- Make the experience pleasant – give treats, such as bits of deli chicken or hot dog. Be careful, however, only to reward good behavior. Do not use treats to distract from a problem, and be sure you are not inadvertently rewarding aggression or bad behavior. If both dogs sit without growling, give a treat - within three seconds. Timing, and an immediate connection to the good behavior, is crucial to make the dog remember and understand what behavior is desired and is being rewarded.
- Remember that dogs are hierarchical. One will be dominant. This is usually the resident dog, but if it is not, do not try to reverse the order they establish because you feel sorry for your dog – that will simply prolong the conflict. A submissive dog is not an unhappy dog – some dogs greatly prefer to let someone else (human or canine) be in charge.
- If the dogs get into a minor tussle, as long as neither one is getting injured, do not interfere. (If you break up the conflict too soon, they may bring more of the unresolved tension to the next encounter.) Simply walk in opposites directions to separate the dogs. STAY CALM!
- Accidents do happen--do not worry, yell, or punish. Simply clean it up and move on. Be sure to give both dogs extra opportunities to relieve themselves outside until he/she becomes accustomed to your routine and schedule. If either dog starts to urinate or mark inside the house, consider consulting a Trainer/Behaviorist.
- Be sure to give your resident dog the same amount of affection he received in the past. Don't give him a reason to be jealous. If he got a walk or a play session at a particular time of day, be sure to continue that. The less the routine is disrupted, the easier this will be.
- If your resident dog is crate-trained, it is best to start that with the new dog immediately. Remember that dogs are den animals – properly crating a dog (correct size, reasonable amounts of time, etc.) is not cruel and may help the dog feel safe and secure. Some dogs prefer solid crates to wire; if you only have wire, put a sheet or towel over the wire crate (but be sure to allow air circulation).
- Each dog should have his own food and water dishes. Leave some space between the new dog's bowls and the resident's bowls. Food can be one of the most competitive areas for dogs – feed them separately if you have any doubts about their relationship.
- Don't overwhelm the new dog with visitors, particularly if he/she is a puppy, during the first days in your home. Remember that change is stressful – allow the dog some quiet time.
Within a few days, the dogs should be getting along nicely, happy to have each other as a friend and pack member.
- Second Hand Dog, by Carol Lea Benjamin.
- The Other End of the Leash, by Patricia McConnell, Ph.D. (2002) with positive training methods; how to use human and dog body language to help your dog understand what you want the dog to do. Also a good read.
- Excel-Erated Learning: Explaining in Plain English How Dogs Learn and How Best to Teach Them, by Pamela Reid.