I've been potty training my Yorkies for 17 months. They are 19 months and still have accidents. They are litter box crate trained and never have an accident in their xpen. They have an outside fenced in area to go in and I walk them also outside on a leash. What is my problem? I don't know what else to do. I have caught them several times and showed them their mistake. I would love to let them run around all day long but that is not a cool idea. Will they eventually get the idea? Any ideas? Oh, they go on the paper things you buy also when there at the Kennel. I don't know if they have mistakes there. She lets them loose during the day sometimes. They have only been twice in two years! but they will be back for 10 days when we go to Hawaii. She also lets them go outside without a leash and they are very good dogs. They fetch, sit, etc. HELP!