A pet door or pet flap is a small opening to allow pets to enter and exit a building on their own without needing a human to open the door. Originally simple holes, the modern form is a hinged and often spring-loaded panel or flexible flap, and some are electronically controlled.

Wall-installed doors are more secure than dog doors installed into a door, and are harder to crawl though. Lock your pet door securely during the day since that is when most burglars are active. The majority of break-ins occur during the day when people are away at work.

Potential burglars can use dog doors as an easy access point into your home. However, dog doors are generally small, and it is quite difficult for an adult to squeeze through, but not impossible. Intruders are more likely to peek their heads through the door to get a clear view inside.

These pet doors come with a panel you can slide in to completely lock the pet door so no pets (or wild animals) can get in or out. Or some, like PetSafe’s 2-way locking cat door, has a lock incorporated into the design of the door and all you need to do is slide it closed.