I have the same problem w/ my son's dog (they are both living w/ me now) and wrote about this before. One suggestion someone here gave was this doggie girdle type thing - well, that's not really what it is but you can buy it at a place like PetSmart or something. It's a harness type thing that keeps their back legs unable to leap over fences. I too have a big fenced yard and my four dogs are fine in it all day. But not Punk that's his name. He doesn't jump all the time but every now and then he just gets this wild hair up his....you know and takes off. Unless I build up the fence to look like a prison camp I have to be out w/ him every time. What a pain. I don't know about electric fences, have mixed feelings about 'em. Have heard both pro and con.... any help from others out here?? Laurie