For the first few days, keep the new cat confined to one room. Provide fresh food, water and litter daily. Make frequent visits to spend time playing, feeding, petting and generally interacting with the new cat during its isolation. Give it time to adjust to this one location, where it is guaranteed emotional and physical security. Meanwhile, your resident cat will sense traces of the intruder on your clothing and skin. The new pet's odor and sounds will alert your resident cat to its presence. During this period, spend extra time with your resident cat, engaging in favorite activities in an effort to relieve any anxiety and minimize tension. Feeding tends to relieve an animal's feelings of anxiety and may help it adjust to the household changes. Place your resident cat's food dish near the door to the room where the new cat is kept confined. Feed them at about the same time so that they are separated only by the closed door. Move to the next step when neither cat exhibits any growling, hissing or spitting when it senses the other is nearby. Next, confine your resident cat, with its own food, water and litter box, to a favorite location. Allow your new cat to explore your home for brief periods. Accompany it on its patrol to extend the comfort of your presence beyond the room where it had been isolated. Several times each day, allow the new pet out of confinement for longer and longer periods. When both cats appear comfortable (the new one will assume positions of rest, for example, or groom itself more than it actively explores your home), proceed to the next step. Arrange to be present when both cats roam freely. This should be planned to coincide with regular mealtimes. Some hesitation and hissing are to be expected from either or both individuals. Feed the cats in each other's presence, placing their food dishes at a comfortable distance. Wait only a few minutes after they have eaten to confine the cats to their quarters until the next scheduled mealtime. If either or both cats seem so disturbed that they do not eat in the other's presence, remove the food bowls and confine each to its own safe place. As things settle down, allow them to spend progressively longer periods together after they have eaten each meal. Move their food dishes gradually closer to each other at successive meals. If problems occur at any time during the introduction process, return to the preceding step as outlined above. With continued progress, you may decide to gradually move one or both litter boxes to another location. It is advisable to maintain one litter box for each cat, even though each cat will likely use both boxes.