He is a very smart dog but I had never truly lost a dog before so I didn't know they came back. I knew cats came back but I have never heard of a dog coming back. My old dog, Buffy, whom was a complete mutt. We had no idea what lineage he came from. We believe he was a mix between a sheep dog, and a lhasa apso poodle. Anyways, he would get out, but he would always trot down the street and we were able to get him by driving down the street and calling him to the car. Dirk, my current dog, my rotty, unfortunately went the opposite direction, and deep into the woods. I was afraid he would get eaten by a large fox, or wolf. But thankfully he did come back on his own and all I had to do was call him and he came to me. :] We love him very much and we are now keeping him behind the metal fence door rather than allowing him access to the shorter wooden porch door. Thanks for the help everyone.