In 1995û96 twenty-three grey wolves were released in Yellowstone National Park where, due to over-hunting, there had been no wolves at all for almost seventy years. This reintroduction project was an overwhelming success. Over twenty years later we can still see the changes the grey wolves brought to Yellowstone National Park. Now that the elk graze higher ground, seedlings are growing tall, rivers are getting deeper as beavers return, and a lively pond ecosystem is developing. This true story offers an important lesson about the difference one creature can make in creating a healthy, thriving world.