One of the surest harbingers of spring is the return of Purple Martins to the houses that people put up across the United States to attract these companionable birds. The bustle of courting, rearing nestlings, and fledging young martins fills the summer months, until approaching autumn lures the martins to their winter range in South America. Then human landlords refurbish their martin houses and wait for another round of this much-anticipated yearly cycle. Robin Doughty and Rob Fergus here present a concise natural history of the bird and its centuries-long companionship with people. They discuss the martin's scientific classification and names, its migration and range, and its family life. They relate stories of how Native Americans and European colonists attracted Purple Martins and how Americans throughout the nineteenth and twentieth centuries helped martins survive the loss of natural nesting sites by providing houses for them. The authors also describe how whole communities have become centres for martin promotion and detail the many organisations and resources in print and on the Internet through which martin fans can communicate with each other and learn more about attracting and housing the birds.