Some of our dogs were trained that way, and some were not. With Freckles, our first St. Bernard, her definition of "our yard" included half of the field next door, but everyone was okay with that. Gracie, the Great Dane, knew where she was supposed to stay, but just adored running as fast as she could - if she slipped past before you could snag her collar, she was off and running - the rest of her was so slick that even if you grabbed her, she's literally slide right through your grasp!