If you decide to get a new kitten when you already have a cat, it's important to know how to best introduce your older cat to the new kitten. Proper introductions may help to prevent territory issues as well as help your older cat get along with the young newcomer.

Keep in mind, some cats are friendlier and won't need very long to introduce a new kitten to, while others, it may take as long as a week or more to introduce the new kitten. When considering how to introduce your new kitten, be sure to keep your older cat's personality in mind.

Isolate
In the beginning, you may want to isolate both cats. Allow your new kitten to explore areas of the house, while separated from the older cat. This will help reduce any anxiety the new kitten may be feeling, as well as leave the new kittens smell where the older cat will pick up on it later. You may want to do this for just a few hours, or even a few days.

Scent Exchange
If you are keeping your cats isolated for a longer period of time, rub each cat with a dry towel and then leave the towel in the other cat's area. This will familiarize the cats with each other's smells.

Visual Introduction
Allowing your cats to see each other, without making contact may help. Leave your new kitten in a kennel or crate, and allow your older cat to sniff and investigate the kennel or crate. Do not allow the older cat any access to the younger cat. The older cat should only be able to see and smell the younger cat. The older cat my hiss, growl or swat at the crate or kennel. This is normal.

Short Supervised Physical Introduction
Once you feel your cats are ready to make physical contact, allow them to interact with one another supervised for a short period of time, no longer than fifteen minutes. You may want to do this when other people are home to assist you. You should keep the cats very close, sitting on the floor with them if possible. Pairing this introduction with cat treats may be beneficial.

Do Not Force Interaction
If your cats do not seem interested in each other, or seem to be avoiding each other, do not attempt to force them to interact. They will do so when they are ready, and forcing them to may cause them to display signs of hostility.

Separate at Signs of Hostility
If your cats begin to show signs of hostility when they are physically introduced to one another, such as hissing, swatting or biting, separate them. Your cats may not be ready to get along quite yet. Repeat some of the steps above until you feel they are ready for another attempt at a physical introduction.

Longer Supervised Physical Interaction
Once your cats have managed to be introduced without displaying signs of aggressiveness, allow them to interact for a longer period of time, up to a few hours. Be sure you're immediately available and close by to separate the cats should they become aggressive with one another.

Day Time Free-Roaming
Once your cats have mastered the above steps and seem to get along with or simply tolerate one another, you should allow your cat to roam freely during the day, but only when you are home, just in case any intervention is needed. If your new kitten is less than 16 weeks old, she should not be allowed to free roam at night or when you are away from home for her own safety.

Full Time Free Roaming
Once your cats have demonstrated that they can get along well, and your kitten is older than sixteen weeks, you may now allow your kitten to roam freely, just as your other cat does!