This article is from the Problem Behaviors in Cats FAQ, posted to rec.pets.cats newsgroup. Maintained by Cindy Tittle Moore with numerous contributions by others.
You may wish to keep your cat off of the furniture or off of a particular piece of furniture. Or to keep them off the counters and or tables. Because of a cat's ability to climb and jump, this isn't always a practical thing to do -- but you can somtimes train them to stay off very specifiic pieces of furniture or locations by covering it with aluminium foil. In most cases, a month of leaving the foil on when you leave the house will be effective.