On a Sunday afternoon in early November, a strange gathering took place in the backyard of Fred Hassen's Henderson area home. More than 15 dog owners congregated, each with at least one dog at his or her side at all times, and though there wasn't a leash in sight, not one of the dogs wandered away from its owner.

Or growled, sniffed, or even acknowledged any of the other dogs. Or even came within three feet of another dog or a person without permission from its owner to "go say hello."