I use a PETSAFE invisible fence. $300 for the kit and another box of wire and flags was steep if you ask me but my girl bought it so I couldn't argue. It works great on both dogs, the black lab and the husky. Both needed to have the longer prongs put on the collars and the maximum "correction" level turned on before they cared about staying in the boundaries. Ralph ran through the fence a few times until he tried it in the snow. water is an excellent conductor and he got knocked on his ass. Now you can't drag either one of them within 10 feet of the invisible fence line. It doesn't matter if there is a stray dog in the road snacking on a pile of free beef jerky, they won't cross the line no matter what. It's real nice with the invisible fence, in the morning I just open the door and they run out. Previously they would run out and over the neighbor's house, onto the school bus, into the forest... Petsafe stands behind their products too, I had a shock collar I was teaching them not to jump on people with and it broke so they sent me another one free. I dropped the transmitter from the free one and ran it over with the lawn mower, I called them again to ask where I could buy just the transmitter and they sent me a new one - no charge! That is unbelievable in today's world.