There are many ways a new cat can become part of your family. Perhaps it was raining and that cat meowing piteously on the street just got into your heart. Or perhaps you realized your kitty was becoming depressed alone at home all day, and decided to get him a playmate.

No matter how or why you’ve gotten a new cat, a proper introduction to your household can make all the difference. Unlike dogs, cats are not pack animals, and they may react badly when strangers appear out of nowhere. That doesn’t mean a new cat will never become a valued companion to your “lonely only.” Cats are still social creatures, and a friend to play with can relieve much of the stress of being alone.

Age and gender don’t matter as much as matching personalities. “If you’re trying to make a good match with your resident cat, think about the types of things your cat likes to do. If he’s a lap cat, you’d be better off adopting a second kitty who isn’t such a lap cat. That way they won’t vie for that limited space,” says feline behavior expert Pam Johnson-Bennett.

If you decide on a kitten, remember that “a kitten doesn’t have a sense of territory yet, so he’s often less intimidating to the resident cats. However, a kitten also views everybody as his friend and may try to get too close to the resident kitties too quickly,” says Johnson-Bennett. In other words, an older cat may not find the kitten pouncing on his tail all the time as amusing as you do.

When you bring the new kitty home, don’t just throw him on the middle of the floor and expect everyone to get along. Instead, for the best results, make it a gradual introduction.

If you rescue a cat from the street, it’s extremely important to have him examined by a veterinarian as soon as possible — and to keep him separated from your resident cat(s) until that happens. Catching a deadly disease, or even a flea infestation, is not a nice introduction! “When bringing in a rescue, you should have a sanctuary room set up that will keep the cat completely separated from the resident cats,” says Johnson-Bennett. “Wash your hands after handling the cat and roll a towel up under the door to keep the cats from going nose to nose in that space.” Provide a litter box, food and water bowls, a toy or two, a soft blanket and a box to hide in.

Even a new cat with a clean bill of health needs to be kept in a separate room for awhile. Cats get to know each other through scent, so rub a towel or sock over your new cat and give it to your resident cat to smell, and vice versa. Eventually switch rooms — still keeping the cats apart — so that the resident cat can thoroughly sniff out the new cat’s things while the new cat explores the rest of the house. After this exercise, you can let the cats meet in person, but be prepared with treats and toys. Don’t be afraid to bribe liberally — the more your resident cat associates the new cat with tuna treats, the better.

It’s very important that each cat has his own litter box, food bowl, water bowl and sleeping place so that your resident cat doesn’t feel like his territory is being invaded. If, despite your best efforts, hostilities do break out, distract the kitties with a play session or strategically tossed treat. As “Clawed” Raines said in the movie Casablanca, that could be the start of a beautiful friendship.