I have a 10 yr old yorkie that also loves to bolt off at every opportunity. We have a long lead in the back yard, the yard is fenced in, but if he gets out the door, he is able to go under the fence

.....I am scared he will get hit by a car or into a fight with another dog and/or other animal. Thanks for the tips, & I will be looking into the book "Let the Dog Decide".