Instructions
Consider a cat that best complements your the personality of the pet you already have. The "introduction" is officially shaped from the minute you go to the humane society and select your new pet. Keep in mind your current cat's personality. If the new cat seems aggressive and your cat is very shy, the new one may be overly dominant and cause your other companion to retreat even more. However, if the cat is active and sociable, it may bring out the best in your shyer cat. Consider this: You know the type of people you get along with best. You wouldn't want to be thrown into a situation where you had to live with someone you didn't mesh with 24-7 against your will, right?
Get your new pet wormed and vaccinated. Make sure the pet has received a thorough medical examination and is up-to-date on all her shots. That way, you won't unknowingly introduce a contagious illness or disease when you bring home the new furry friend.
Make sure the cat is spayed or neutered. (Both pets should be.) This is just part of being a responsible pet owner, but it also makes for a better coexistence. The fear of a same-sex power struggle won't be such an issue if both pets have gone through the appropriate procedure. You are asking for domination issues, though, if you bring an un-neutered male into the household with another male cat. The same goes for females.
Start off by confining the new cat to its own room. The biggest mistake pet owners make is automatically throwing the cats together. You want to allow them to gradually get to know each other's sounds and smells. Cats are extremely sensitive, especially to changes in their environments, so move slowly. Separate the cats for at least one day. Ideally, sequester your old companion in the room for a few days and allow the new cat to explore the home.
Let the cats "duke it out" in the early stages of the relationship. (Well, up to a certain point.) This is a natural part of acclimating to each other. However, cats can also be extremely vicious and "go for the jugular" during fights. Monitor this behavior closely. If you have taken the appropriate measures so far by gradually introducing the cats, this fighting should not go on for longer than three weeks.
Allow the cats to each maintain their own space. For example, each cat should have a separate space for its own water bowl and its own food bowl. You can slowly move the bowls closer together; but just as you have your own sanctuary, cats should, too. Litter boxes should always be kept at a distance from each other.
How to Introduce Another Cat to the Household
As any cat owner knows, our feline friends are extremely sensitive, especially to changes in their environment. That's why doing something as drastic as introducing another cat to the household requires a lot of thought and careful planning. The way in which you introduce this new pet will determine your pets' relationship for years to come. If you introduce the new animal recklessly, the two may never get along.