Tinfoil has never worked for me. Our problem is w/ our cat getting up on the table. It's kind of gross to have the cats on the dinning room table and she sheds on the placemats etc. But anyhow, we tried laying tinfoil out and she just went right up and went to sleep on the tinfoil. She jumps down as soon as we come into the room, or hears us coming, but it's annoying. Sometimes, cats will be cats.