Dogs at Large
In this article, you will find:
Underground fencing
A lot of people seem to be latching on to underground fencing as a relatively cheap, easy way to confine their dogs. An electrical wire attached to a transmitter is buried underground around the edge of the area where you want your dog confined. Your dog wears a collar with a receiver and electrodes that are in contact with his skin. When he approaches the boundary, the collar beeps a warning. If he gets closer, he gets an electric shock. He has to be trained to understand that the beep means a shock is coming and that he can prevent it by backing off.
There are some serious problems with underground electrical fences. If your dog has a high pain threshold or sees something that really motivates him, he'll risk the shock (or forget about it) and cross the wire. Once he's out, he won't want to cross back in because the motivation isn't strong enough to outweigh his fear of the shock.
Another problem is that an underground fence doesn't keep anything from coming into your yard. Your dog is vulnerable to attack by other dogs and teasing or even theft by kids and adults. You also open yourself up to legal and financial liability if someone comes onto your property and is bitten.
A dog charging up to the edge of a hidden fence system can be terrifying for people passing your property. When a dog charges a conventional fence, people know the fence will stop him. If he charges the edge of a hidden fence, a passerby may not know that he's fenced at all and cannot know for sure that the fear of a shock will hold him. This is particularly a problem for anyone walking by with a dog. Believe me, it's heart-stopping to have a dog charge you with no visible barrier in sight, and letting your dog do that is not a nice way to treat your neighbors.
If you must resort to an underground electrical fence, I suggest you keep the perimeter well away from sidewalks or other places where people walk or ride bicycles, and that you allow your dog to be out in the yard only when a responsible member of the family can be there with him.