Like other livestock in the Rocky Mountains, sheep need protection from predators, such as coyotes and wolves. Guardian dogs help ranchers protect their flocks. But they are not the typical herding dogs, and they are not native to the region. The breeds were imported from Europe, where they have been guarding livestock for thousands of years. As puppies, they are placed in fleece and learn to identify with the smell of sheep. It isn't long before they meet their first sheep and mingle with the flock. With little training, the dogs instinctively know that their job is to keep a lookout for danger and now and then do some babysitting. Cat Urbigkit's engaging photo-essay shows how guardian dogs form a bond with the sheep that lasts throughout the dogs' life.