Using a Pet door allows you the freedom to control when and where your pet travels. If you've never thought about using one, take a moment to review these reasons to consider it:
Convenience
Pet doors eliminate the need to accompany your dog each and every time they need to go out. This routine can affect your life in dramatic ways. Using a pet door, you can allow your pet access to the outdoors for a number of reasons, but we feel the number one reason would be, their ability to allow you the chance to sleep in without worry, as your dog can used the door to relieve themselves whenever they may need to.
Comfort
If you leave your pet home alone all day while you're at work, your pet will have to "hold it" for a long time, which can be uncomfortable at the very least. Fewer accidents Puppies and older pets, have a much harder time controlling their bladders for long periods. Access to the outdoors may help to eliminate the occurrence of accidents in your home.
Exercise
Many pets don’t get the necessary exercise they need. Allowing your pet access to the outdoors provides them the opportunity to exercise more, which leads to slimmer, healthier pets. Door-Scratching Pet Doors help eliminate the irritating and often destructive scratching many dogs opt for, when requesting your attention of their outdoor needs.
Stimulation
Sights, sounds, and smells from outside provide your dog with excellent mental stimulation, which can help to keep your dog acting younger and more alert.
Mike Steele
http://www.dog.com