When our golden retriever got to be 6 months old I thought he was going deaf because he damn sure acted like he didn't hear me most of the time. We live on 6 acres with plenty of room to roam when we were out but he needed to learn the boundaries especially the pretty heavily traveled road 70 yds to the front of our house. I finally purchased a Garmin collar in hopes of protecting him from himself. The first thing I did was put it around my leg and turn it to it's highest setting to see what it felt like. I then used it with him very lightly( his hearing came back immediately, it was a miracle) for about 3-4 months and it worked very well for him. So much so that for the next 6 months after I would have my grandaughters put his collar on when they would take him for a walk around the property but not even turn on the collar or take the controller with them. He was very attentive when he had his collar on as a young dog. He never had a collar on for the last 8 years of his life and was an extremely obedient dog that knew all of his boundaries on the property and never violated them even once no matter what was distracting him. There was a days old fawn 20 feet from our property line that he really wanted to go check out but he stopped like there was a border wall payed for by Mexico in his way. We had to have him put down this past October, still really hurts.