Always. I was walking my dog and I passed a house a guy was coming out of. I said goodnight and kept it moving. Keep in mind, my neighborhood is very dark at night. So I’m walking, and my dog keeps on turning around making that huff noise that they do. I’m just Aggie and not paying attention. So I’m yelling at her telling her to calm down, but she keeps on doing it. Finally I turn around and the guy was walking several feet behind us, but was making a point to be quiet. He tried to slow down but he was literally walking in my footsteps and his expression looked surprised that I caught him. She was alerting me to the fact that that guy was still behind me. Dogset all day.