How Do We Make Our Schnauzer STOP?

by Sue
(Roswell, USA)

We have a mini schnauzer, 4 years old almost 5. He's a great family dog and very loving.

What is the best way to train him to stay or stop before bolting out the door? He is very enthusiastic when we get home and does a circular run outside, part of it is onto the road within our community.
We try and look out for cars but am scared one day a car will hit him.
While we walk him on a leash he loves running free and doesn't always stop when we call his name.
He is good natured, great protector of the family and a great joy to have.
Our issue is that we don't want to curb his enthusiasm, but we want him to stop when we use that command.