Pets do everything with us. They celebrate our birthdays, eat our leftovers and warm our feet at night. They want to be everywhere we are, so why not let them?

Traveling, with its tight spaces, endless lines and long hours can already be a headache. Throw in a four-legged friend and all the planning, scheduling and booking can be enough to make you want to stay at home. Planning ahead is imperative for making your journey as stress free and enjoyable as possible. If you decide to pack up your pet, there are a few things you need to know to make the road ahead as smooth as possible.

Take a Trip to the Vet

Most pets, like their owners, hate going to the doctor's. But, a trip to the vet is key to insuring your pet's health, safety and wellbeing. Make sure your pet is up-to-date with vaccinations, especially rabies, as these shots are legally required everywhere you go. The vet may also test for heartworm and give other vaccinations including bordetella, parvo, and even lyme disease, depending on where you're headed. Let your doctor know your destination, duration, and means of transportation to help to know the best way to keep your pet healthy.

For domestic flights, some airlines require a health certificate acquired within 10 days of departure. For international flights, it's wise to make an appointment with a doctor six months in advance, as different countries have different restrictions and requirements.

A veterinarian may recommend sedation for a longer trip, especially for an animal that's anxious or aggressive. If you decide to sedate your pet, make sure to test the medication you are planning to use before the day of departure. This will familiarize your pet with its effects and let you know how they respond to the medication.

Invest in a Quality Crate

Whether you are traveling by plane, train, boat or car, you will need a sturdy, properly ventilated crate. There should be enough room inside for your pet to stand up, turn around, and lie down comfortably. To prevent blocked ventilation, make sure the crate has knobs or a rim at least 3/4 inches (19 mm) on all sides to insure airflow. The crate should have a door that securely latches and have handles or grips on the outside for easy lifting and transportation. The bottom should be leak-proof and covered with a towel or other absorbent material.

The crate should be clearly labeled with your pet's name, your name, address, and a phone number for both your home and your destination. Write all of this in permanent marker on multiple sides of the crate.

Traveling by Plane

Airports are a hassle already, but traveling with a pet could mean extra time and planning. Give yourself plenty of time to check in, go through security and find your gate. Even for domestic flights, arrive at least one and a half hours early as unforeseen conflicts might arise with your pet.

If you have a small dog or normal-sized cat that can fit comfortably into a carry-on pet case, you may be able to have your pet travel with you in the passenger cabin. If your cat or dog is small enough (typically under 10 lbs (4.5 kg)) to travel in the cabin, the pet carrier must be small enough to fit under the seat and should provide enough space for your pet to turn around and lie comfortably.

Some airlines have a maximum number of animals allowed as carry-on luggage in the cabin with passengers, so be sure to register your pet ahead of time.

Several airlines have also implemented a pet embargo that restricts animals from flying in cargo during extreme temperatures (over 85 degrees (29 C) or under 35 degrees (1.7 C)). Before booking any flights, be certain the airline has no special restrictions that will prevent your pet from flying. Also, consider booking a nonstop flight versus one with several layovers. This may be more expensive, but it's safer and less stressful for you and your pet.

If you have a large breed dog, you will have to check him or her into the cargo hold. But, if you can't bear the thought of putting your large pet in the belly of a plane you may want to check into pets-only flights like the ones offered on PetAirways. These flights may be cheaper, and allow your pet to fly comfortably in the cabin.

Either way, flying with a pet is not cheap. Expect to pay almost as much for your pet's ticket as you paid for your own. For example, Delta Airlines currently charges $150 for a one-way, in-cabin flight for your pet. Expect to pay even more to stow your pet: One-way costs for checking your pet as baggage in the cargo hold is $275 for travel within the U.S. and $550 for flights outside the U.S.

Traveling By Car

If you are planning a road trip, a pet could be the perfect companion. However, there are some precautions to take to insure a smooth ride. Just like humans, pets need a seatbelt. This could mean a pet crate, a dog harness connected to a seat belt, or a divider to keep your pet in the cargo area of a van or SUV. For most of the trip, your pet should not be loose in the car.

Even if your dog is secured by a harness, make sure his head remains inside the car. If it's hanging out of the window, his eyes and head are at risk of being injured by debris.

However you secure your pets, always take them with you when you park. Do not leave them in the car, even if the windows are rolled down; a car can heat up to a degree much higher than the outside temperature.

While most cars can carry pets, some are better at it than others. A general rule of thumb is that the larger the vehicle, the better. Minivans are popular because you can put crates in the back. If you have a small car or a large pet, it may be advisable to rent a larger vehicle to make sure your pet is comfortable.

Where your pet sits in the car can also play a role. Yes, pets can get carsick too. The closer your dog is to the front of the vehicle, the less motion there is and the less likely he or she is to get carsick. Consider placing your pet's crate near the front.

Crossing Borders

Traveling internationally with your pet? Pet immigration rules are specific to each country worldwide, and pet owners need to be familiar with these rules before traveling to avoid pet quarantine in countries that require it. Pet owners should create a pet passport, which is essentially a collection of all identifying and required documents for entering a given country. Also, familiarize yourself with pet immigration rules and procedures for less hassle when you cross the border.

All EU countries require an International Health Certificate to be issued by your veterinarian as near to the date of travel as possible but not more than 21 days before travel.

Some countries also require your pet be micro-chipped upon entry. This can be extremely helpful if your pet is lost or stolen.

Hotels and Lodging

Congratulations! You made it! But don't get too comfortable yet. Don't assume your pet will be allowed in every hotel room. Instead, call ahead or check on the hotel's website to make sure it is a pet-friendly place. This can prevent you and your pet from encountering any unpleasant surprises when you arrive.

If you forgot to check with the hotel or don't have any specific lodging in mind, Red Roof Inn, Motel 6 or Days Inn have locations across the United States and are known for welcoming pets. Or, you could stay at any of the over 475 KOA Campgrounds, all of which accommodate pets. If you are traveling in Europe, Best Western, Marriott and Choice Hotels, as well as many more independent hotels, offer pet service.

Once there, be respectful of other guests, employees and the property. Always keep your pet on a leash unless otherwise noted, try to minimalize barking, and always clean up after your pet. Be mindful that not everyone loves your pet as much as you do.

After you've settled in, take advantage of the outdoors. If you are near a local or national park, take a walk with your pet and explore some of the trails and paths. If you are by the shore, pet-friendly beaches are a great place to play fetch or go for a run. Find a dog park nearby or find out if your hotel has any pet activities planned.

Have any more suggestions? Feel free to share them in the comments section.