Does your pet relieve itself in the house? Does he sit at the window, meowing and whimpering to go outside? If you answered yes to any of the above questions, it may be time to get a pet door. They are a great way to allow a pet access to the outside with the convenience of not disturbing the owner. This will also lessen the stress a pet may feel if they are left at home alone all day while the owner is at work. There are several factors to consider when choosing a pet door. Placement of it is one of the initial factors to think about. Do you want your pet to have access to the entire yard, or only to a run? Doors, of course, are the usual place to install one, but there are also numerous specialty options available that can be installed in other places. The thickness of the area in which you are installing it and the size of the pet will affect which one the pet owner selects. Most of them on average will allow the use of a door that is up to two inches thick. If your door is over two inches thick or you are installing it in a wall, consider a tunnel that can be built to cover the openings between the outside and inside frames. This can prevent your pet from getting its legs stuck. If you install a pet door into something where the thickness is greater than four inches, your pet may refuse to use it. Cat and dog pet doors vary in size and shape. Most of the cat variety will conform to the cat's shape, while a dog one will usually be square or rectangular. Dog option will vary as well due to the dog's weight and the width of the dog's chest. There are many different styles of pet doors now available today. Some of these include ones that are installed in windows, walls, and regular and sliding glass entryways. There are even electronic ones that lock. These selections are controlled by a collar worn on the pet that senses when the pet is close to it and releases a lock so the pet can come inside. It will them immediately lock behind the pet, eliminating other animals coming inside your house. This automatic release only works on the outside of the home. These are great choices for someone who is concerning with home security or has a large number of stray animals in their neighborhood. This pet item comes in all colors and materials to match your home. Many online pets store now offer ones beyond the basic plastic flap. Consider researching the internet to find a style that best suits your preferences for design, color, and location. No matter what pet door you decide is best, be sure to regularly check to see that your pet can easily fit through it. If your pet has gained weight, you may need to install a larger one to keep your pet from getting stuck.