A tapestry of heroism, betrayal, tragedy, kindness, abuse, and unique companionship, this history from the author of How the Dog Became the Dog looks at how we have relied on canines in shaping the American continent, while examining how that relationship reflects who we are at a given cultural moment. Mark Derr explores the varied roles of our best friends—including dogs who pull sleds, help in wartime, and serve as guides, as well as show dogs and bomb-sniffing dogs—and recounts the exploits of such canine characters as the notorious San Francisco street dogs Bummer and Lazarus, and FDR's Scottish terrier Fala, who still stands first among "presidential" pooches.