Take Fido on vacation, but be sure to go by the book when you make plans and reservations.

If you want to cash in some frequent flier miles and take your dog along, you need to know the rules. The United States Department of Agriculture (USDA) requires dogs who travel by air to be at least 8 weeks old and weaned from their mothers.

Most states require health certificates issued within 10 days of your arrival, and that your dog's rabies vaccination be current. Some states - including Hawaii - and many countries require an extended quarantine as well.

The individual airlines set the rest of the rules for themselves, so you'll need to check with your airline to learn what they allow and require.

Getting a Seat Assignment
Make sure to ask where on the plane your dog will ride. Airlines often allow smaller dogs to travel in the passenger area with you. If you choose this option, your dog must ride in a carrier that fits underneath the seat in front of you.

Larger dogs must travel in the cargo area of the plane in USDA-approved carriers. These carriers should be strong, well-ventilated, and just big enough that your dog can stand up, lie down, and turn around comfortably. Be sure to put your dog's blankets and toys in his carrier. He'll be alone in strange place, so he needs all the comfort he can get.

Make sure to mark your name, your dog's name, your home address and telephone number, plus the address and telephone number of your destination on the carrier. If your dog will ride in the cargo area, write "live animal" on his carrier in large, clear letters.

Making Reservations
When you book your ticket, make a reservation for your dog too. Be aware that you may be charged extra for your "special baggage."

Book your tickets as early as you can because some airlines limit the number of animals per flight they allow to travel in the passenger area. And try to get on a nonstop flight so your dog won't be shuffled around if he's traveling in the cargo bay.

Also avoid taking your dog with you during heavy travel times like holidays and weekends. There's a great chance for more delays, mix-ups during these busy times. Also avoid taking your dog on a plane during extremely hot or cold weather. The climate in the cargo area is usually not as temperate as it is in the passenger area.

To Feed or Not to Feed
Don't give your dog any food eight hours before the flight or water two hours before the flight to help cut down on motion sickness. (Puppies are the exception: They can develop dangerously low blood sugar if you withhold food.)

You can give your dog a little water during layovers, but the Federal Aviation Administration requires that animals stay contained at all times, so don't let your dog out of his carrier.

What a Knockout
Only give your dog a tranquilizer for the trip if your veterinarian recommends doing so. It can be dangerous to tranquilize dogs traveling in the cargo area because the drugs can make it hard for your dog to regulate his body temperature.

Communication Is Key
Many airlines require vaccination and health documentation. So be sure you take your pooch in to see your veterinarian before you leave. And tell the flight crew if you have a dog in the cargo area. They can help make sure your pet gets the care he needs in case of delays or emergencies.