Every kind of cat, from lions and cheetahs to Siamese and alley cats, have an instinctive need to scratch. Scratching behavior serves three functions: marking territory, keeping the cat's claws in proper condition, and stretching the muscles and ligaments in the toes and feet.
Declawing (the surgical removal of the first joint of the cat's toes, which includes both the nail and the cells from which new nails grow) does not stop scratching behavior, although it tends to reduce the amount of damage the cat can do. Your goal, then, is not to stop your cat from scratching -- that can't be done -- but rather to limit her scratching to the places you choose.
Give her a good scratching post -- or two, or three. Remember the three reasons for scratching, and get a post that meets all those needs. It should be tall enough for an adult cat to reach up and get a good stretch. It has to be sturdy enough that a 10- to 15-pound cat repeatedly pulling on it near the top won't bring it toppling over on her head.
This would be a quick way to train her not to scratch on the post! The post should be covered with a nubby, coarsely woven fabric that shows scratching damage, such as sisal cloth. Cats are attracted to textured surfaces as scratching zones, and the coarse weave lets them hook in and get a good stretch. Being able to see the results of their handiwork reinforces the territory marking part of scratching. These are the absolute basic requirements for a proper scratching post.
Put it in plain sight. Remember the last time you were looking for a particular address and none of the houses were clearly marked? You probably muttered to yourself, "Why don't they mark these things so people can see them?" Your cat's scratching damage is how she marks her territory -- her address, so to speak.
If the scratching post can't be seen from cat height (about six or seven inches off the ground) and from many angles in the room, your cat is more likely to ignore it and make her statement on your couch or carpet.
Take temptation out of the way. Try to structure your cat's environment so that the scratching post is the most accessible and attractive thing to scratch on. If you're committed to a lifetime of having cats, it's probably better to outfit your home with washable area rugs and hardwood floors than wall-to-wall deep-pile carpeting in every room. Likewise, furniture upholstered with textured weaves and wicker are almost certain to sustain scratching damage; if you know you'll always have cats, pick another decorating scheme.
Of course, there is an old-fashioned, tried-and-true way to keep cats from scratching expensive draperies, furniture, and carpeting: Put those pieces in one room, shut the door, and allow the cat to roam only in the other rooms.
Pause for claws. Trim your cat's nails regularly to reduce her ability to inflict serious scratching damage. If you're squeamish or your cat is particularly uncooperative, you can have your vet or groomer do it for you.
Hide the damage. If your cat has already done some scratching damage, block it from her view. This means putting stereo speakers on high shelves, covering afflicted pieces of furniture with a sheet, or removing items behind closed doors. The good thing about scratching damage in inappropriate places is your cat has identified the locations she thinks are best for scratching. Once you cover or remove the damaged items, put a proper scratching post next to it or in its place.
Make some corrections, but accentuate the positive. Employ the spray bottle or squirt gun to correct occasional scratching in undesirable locations. Use positive reinforcement techniques to encourage your cat to use the scratching post exclusively: Dangle some toys from the top and encourage her to climb the post or bat at them; scrabble your fingertips on the fabric of the post to get her to start scratching there; physically remove her from scratching in an in- appropriate spot and place her paws in scratching position where you want her to go. In all cases, lavish her with praise and petting for doing the right thing.

When to Call the Vet

Scratching behavior rarely has a physical cause. However, your vet can help you determine a course of treatment or refer you to a competent behaviorist.
If you have a cat that immediately darts under the bed whenever you walk into the room, you might be wondering you got a pet in the first place. Move on to the next section to learn how to deal with shy or skittish cats.