Many cat owners and vets alike have differing opinions on declawing.
Declawing a cat is a highly controversial procedure, and more and more veterinarians do not offer the service. Many countries around the world as well as some states in the United States have banned this procedure as it is deemed unnecessary and inhumane. Declawing is an irreversible procedure involving major surgery, with equally irreversible side-effects that can (and in many cases, do) effect a cat for the rest of its life.
Declawing surgery is actually the amputation of the first digit of each of the cat's toes. The claw is tightly attached to the bone, so much so that it is impossible to remove the claw on its own, so the bone attached to the claw is removed as well. In human terms, it would be the equivalent of chopping off each finger tip at the first knuckle. This severs muscle and tendons which causes much pain and discomfort to the cat, and can cause early arthritis and other problems to the cat's muscles and joints from being unable to walk in a natural position, or no longer being able to stretch the muscles in its back, legs or shoulders from scratching a scratching post.
Aside from physical complications, there is a risk of a declawed cat develop behavioral problems as well. Cats use their claws to defend themselves, so a declawed cat can become very stressed, nervous or even aggressive. Some will resort to biting as they have no other line of attack or defence. Many declawed cats are often surrendered to animal shelters because of this.