Plan your schedule so as not to stress the pet. Periodically let it relieve itself. Avoid leaving your pet alone in the car. If you must do so, put the car in a shady spot, leave the windows open two or three inches, and check on the animal periodically. Always provide access to plenty of fresh water.
Some countries require only health and vaccination certificates.
Some require a six-month quarantine of animals, making a vacation with a pet prohibitive. Once you've experienced the pleasure of a pet's company on vacation adventures, you'll want to be able to do it again. Practicing good pet owner courtesy is the best way to keep the welcome mat out. Never leave your pet alone in a hotel room, where lonely cries will annoy other travelers, or at a campsite where it can taunt or be taunted by wildlife and other campers. Clean up behind your pet at camp sites, at rest stops, on walks and hikes, and everywhere you go.