And although an electric fence is designed to keep your dog in, it does however NOT KEEP OTHERS OUT.

the vet I work for got onel. One day he sent 2 of the kennel helpers to his house to pick his dogs up to bring to the clinic. He forgot one thing. He did not tell the kennel staff about it and they drove through the fence area with the collars on. When they got back to the clinic they told him how the dogs barked and whined when they left his house. and where all over the truck acting wild. He went back to look at the dogs and noticed the collars. ouch for the dogs.