It's often said, "two cats are better than one," and I can't think of anyone that would disagree.

In many cases, two cats are brought home as a package deal as kittens, and the transition from shelter or other situation is quite easy.

Some families decide to adopt a second (or even a third) cat at a later time, and this arrangement changes the dynamics of the process considerably; great care needs to be taken from the start to make the introductions right and to keep the peace.

So, just how do you introduce a new cat into the household without emotionally scarring the animals for life or causing great physical harm?

It's possible!

Keeping in mind that the resident cat has already established who it is in the house, and where it fits in, is important. Imagine how hard it can be for a newcomer to try and carve out a place in the family. It's scary!

As I have always maintained, cats are always more attached to their environment than their people. Usually, if all is well with their home — their "core" — then they are okay, too.

A great start to the process is to have a friend bring in the new kitty into the house, inside a kitty carrier and directly to one room (what I call a "safe room") set aside with the new cat's own litter box, food, water and a comfy bed with a small blanket. Why a friend? Your resident cat won't necessarily associate you with bringing this strange cat into the home — which is a good thing!

It's recommended that your new cat be allowed to acclimate to its new surroundings for a period of one week before attempting any in type of interaction with your resident cat, so keeping it confined to its safe room is essential.

A Feliway diffuser or spray is helpful in quelling any angst that any cat involved will feel during this transition. Feliway is a synthetic pheromone that helps cats feel a sense of well-being and can be found at pet stores. Click here to read more.

Spraying doorways and furniture where the cats encounter each other with the product can help ease tense introductions.

After that one-week period, begin feeding the resident cats and the newcomer near either side of the door to the safe room. Gradually move the dishes closer to the door until the cats can eat calmly directly on either side. At that point, you can use two door stops to prop open the door just enough to allow the cats to see each other, and repeat the whole process.

Swap sleeping blankets between the new kitty and resident cats so they have a chance to become accustomed to each other’s scent before coming face-to-face.

Once the new cat is using his litter box and eating regularly while confined, it's important to let him have free time in the house while confining the other cats. This switch provides another way for the cats to experience each other’s scent without a face-to-face meeting. It gives the newcomer time to become familiar with his new digs without being frightened by other animals.

Avoid any interactions between the cats which result in either fearful or aggressive behavior. These responses can be difficult to change once they become a regular behavior. If either cat becomes very frightened or aggressive, separate them, and continue the introduction process in a series of gradual steps, starting from the beginning.

You should expect some hissing, growling and spitting.

If a fight breaks out, be careful to not interfere directly, as you could become injured. Throwing a blanket over each cat and wrapping the blanket around them before picking each one up is a much safer way to diffusing a tense situation. Separate the cats until they have calmed down.

More considerations:

• Leaving the kitties safely separated in different parts of the house when you are away is best, until you are sure they are getting along reliably.
• Add another litter box and scoop all of the boxes more often. Watch to ensure that none of the cats is being “ambushed” by another while trying to use the box.

For more on this and other considerations for changing dynamics in your pet's life, click here for a helpful guide on feline behavior from Ohio State University's Indoor Pet Initiative.

Lorrie Shaw leads the pets section for AnnArbor.com. Catch her daily dog walking and pet sitting adventures or email her directly and subscribe to AnnArbor.com's email newsletters.