I play this (and lots of other recall games), but have some variations. This one works best with two people. Inevitably, the dog learns that bopping around from person to person earns reinforcers and will start to run towards the other person before he/she is cued to do so. When that happens, wait for the dog to get halfway there and have the first person call the dog back. Do this every time the dog moves before being cued. With a group, you can have a person with an inaccessible handful of food standing in the middle. The dog has to ignore that person and go to the person calling. Of course, the dog should get more than one reinforcer for something this hard, maybe 20 seconds of food, praise, affection, play etc. That starts the process of adding distractions and you can change the distractions up as the dog gets better. Food in a screened off food bowl, toys, balls, any of these things can easily be added to the mix. Heck as the dog gets really good, create an obstacle course for the dog to get through. Again, heavy reinforcement when the dog gets to the person calling. Let me add one more thing. I always include a collar grab in my recalls. So: “Fido, Come,” dog comes, grab collar, click (with the hand NOT grabbing the collar), let go of the collar and reinforce for 20 seconds. Make sure the clicker is not near the dog’s ears. This helps desensitize the dog to a collar grab and lessons the chances that said dog will turn and bite the hand that grabs the collar in a high stress situation.