Long gone are the days when pets had to be left behind while owners traveled during the holidays. Nowadays, there are plenty of airlines allowing pets to travel, some of which will even let cats and dogs hang out in the cabin with their owners. However, before boarding a plane, ship or bus with an animal, there are few things owners may want to take into consideration to keep their animal safe and healthy during holiday travels.

Not knowing proper requirements and rules for traveling with a pet could not only lead to a big headache but also result in a ruined vacation. Such was the case of a Canadian woman who was refused entry into New Zealand after she smuggled her four-year-old cat across the Pacific Ocean on Thursday. The woman reportedly hid her cat in her handbag during her flight but was forced to turn around and fly back to Canada when border agents discovered the animal at Auckland Airport.

Here are a few tips to keep in mind while traveling with a pet during Christmas time below:

Bring a pet’s health certificate: Whether traveling across state lines or internationally, states and countries require travelers to have proper identification for their pets provided by a veterinarian, according to American Veterinary Medical Foundation. A certificate of veterinary inspection ensures traveling pets aren’t carrying illnesses or parasites that could potentially be dangerous to people, animals and the environment in the destination area.

Know airline rules: Most airlines allow small cats and dogs to accompany flyers in the cabin for a fee. Make sure the animal meets size requirements, whether they’re flying in the cabin or in a cargo hold, and call ahead of time to let airlines know a pet will be onboard as there are limits on the number of animals allowed to fly. Be aware that air travel isn’t the healthiest option for pets in certain cases, especially for cats and dogs with brachycephalic or pushed-in faces like bulldogs, pugs and Persian cats. The Humane society recommends chatting with a veterinarian before traveling to find out whether about health risks for pets and how to prevent a pet from catching canine flu and other contagious diseases that could be passed along from other animals in cargo holds. For more information on pet rules for specific airlines, visit here.

Have the proper carrier: An animal’s comfort shouldn’t be in jeopardy whether the pet is tucked away in a cargo hold or in the backseat of a car during Christmas travels. Make sure carriers are in line with airline requirements but are also the appropriate size for the pet. If a road trip is on the holiday agenda, make sure cat and dog kennels are buckled in tightly to ensure a smooth and safe trip.

Pack for pets: A person wouldn’t travel during the holidays without packing properly for themselves, and the same thing should apply for pets. Make sure animals have an enjoyable and comfortable stay at Christmas destinations by packing up food, favorite toys, first aid supplies and pet identification.