There are many nuances and individual personalities which are being dealt with when you bring a new dog into a household already occupied by one or more cats. This article is not meant to be all-encompassing on the subject, but is written to give you some basic guidelines to help make the transition smoother, more peaceful, and ultimately a happy one.
First of all, you will have more control of your dog if he knows a few basic commands first. I know it is not usually common to have the opportunity to train a dog prior to entering your household, but if you have that opportunity, take advantage of it. Otherwise, begin obedience training with your new dog on his first day of arrival.
I have found that changing the cat's living arrangement a few weeks (or at least days) before the dog gets there helps the cat. The cat should have their food and litter up and out of the way. They should have "safe" places to be such as counter tops, shelves, etc. Some people have a kitty door to a room in the house where the cats can go and not be bothered by the dogs. Even dogs that don't constantly chase cats can still bring undue stress to some cats. The kitty door gives the cats a safe refuge without you having to worry about baby gates, etc.
I recommend that the cat be given free reign of the house (or what ever is usual) when the dog comes home. After the dog has explored the new house, it is best to confine the dog to a room (with some one in it with him) and let the cat smell where the dog has been in the house, under the door, etc. Also, pet the dog and let the dog lick your hand - then let the cat smell your hand. And vice versa. I have not found it to be advantageous to try and "stage" a meeting of a dog and cat unless one or both of them is very young. If they are too adults - it is usually best (after the initial dog's confinement to let the cat smell stuff) to let the dog out and about. The cat will usually sit up high somewhere and stare or glare at the dog. Sometimes it takes hours or days before the dog even sees the cat. But they should be supervised at all times until they meet. Many times a cat will bop a dog on the nose - or even claw him. When this happens I find the best thing to do is to take the dog's mind off the incident by playing with him. It is not a bad thing for a cat to bop or claw a dog. The cat needs to establish its place in the house and the dog sometimes needs to learn that they need to respect that cat. Don't punish or give any attention to the cat if he bops or claws the dog. Simply give attention to the dog to take his mind off of it. It is the cat's right to protect itself, and to show the dog (or pup) who he's dealing with.
I find that teaching dogs the "Leave It" command along with the other essentials (sit, down, come, stay) it is much easier to control a situation of dogs and cats. If the dog learns the leave it command and the owner uses it, the dog knows what is expected of him. If he doesn't know what is expected of him, how can he be doing wrong? Chasing cats can be quite fun and entertaining for a dog. If he doesn't know that anything different is expected of him there is no reason for him not to do it.
Here are some basic guidelines for the introduction and living arrangements:
1. Bring a blanket that the cat has slept on to the Humane Society for the dog to smell. Likewise, bring home a cloth or soft chew toy that the dog has been with for the cat to smell. If the cat hisses when he smells it, have second thoughts about bringing the dog into your house.
2. Establish "safe" areas for your cat including sleeping, eating, and eliminating areas, but also other areas for playtime, being social with the family (counters and shelves) etc.
3. Bring the dog into the household and let him explore for 10 - 30 minutes. Then confine the dog in a room with a person in the room with him to keep him company. Then, allow/encourage the cat to go around the house and sniff out this new dog. Then, bring the cat to closed door and allow him to sniff under it. If the cat wants to run away - let him. Don't force the cat to do anything.
4. Then let the dog out and let them be. Don't stage a meeting unless one or both is very young. If possible, you can hold the cat to your chest so that he's looking over your shoulder. At the same time (without the cat realizing it) you can give the dog a quick sniff of the cat's tail in front of you. This sometimes proves useful in attempt to allow the dog the sniff that cat, which is usually something dogs want to do quite badly.
5. Say the dog's name and the cat's name to each of them. I believe that when they realize and learn the name of the other animal they realize that it is part of the family and tend to respect it more.
6. Give the dog perceived responsibility for the cat. Talk to your dog as you would a person - and tell the dog that they need to "take care of Kitty." Tell your dog that he needs to help protect Kitty. Use the cat's name and talk as if your dog understands you. This doesn't always make a difference in some highly prey-driven dogs; however dogs have a sense perception that sometimes cues in on this type of communication and owners see a different type of behavior from their dog relating to their cat.
7. Feed the dog and cat at the same time in places that are relatively close. For instance, the cat could eat on the counter while the dog eats on the floor by the counter. By coming together to eat, they will be developing a social habit that has bonding qualities.
8. Never punish the cat for his actions unless he really tries to beat up the dog.... then a "time out" might be a good idea for the cat and give you time to assess the situation. Most of the time the cat is merely executing his right for respect by showing the dog he's got more than the dog thinks.
9. If the dog lunges, pounces, or chases the cat - give the "Leave It" it command, pull the dog away from the cat (if need be) and *praise* the dog for Leaving It and give the dog a food treat. Yes, praise even when you have "helped" him leave it. He needs to learn the command and that leaving the cat alone is a better thing than chasing or pouncing it. Food usually suffices. Wouldn't it be wonderful if your dog-chasing cat began looking to you for food when the cat comes around... instead of chasing the cat?