Obviously horses don’t hug one another like primates;)  However, I like to hug my horse and thought it would be nice if he knew how to hug back, so I decided to teach him using the clicker. I started with him putting his head over the fence and allowing me to hold his nose in place, c/r. Once he had that he naturally arched his neck a bit more and I slid my arm over his nose, c/r. Then I built duration by extending the time a few seconds or so that he left his head in the loop of my arm, c/r. And voila! I have a solid hug behavior that I now use everytime I leave the farm. I used to just throw a few treats in his bucket as I left, but now I can ask for a mutually reinforcing behavior and pay him for it.