Peregrine falcons have their share of claims to fame. With a diving speed of over two hundred miles per hour, these birds of prey are the fastest animals on earth or in the sky, and they are now well known for adapting from life on rocky cliffs to a different kind of mountain: modern skyscrapers. But adaptability only helps so much. In 1951, there were no peregrines left in Illinois, and it looked as if the species would be wiped out entirely in North America. Today, however, peregrines are flourishing. In The Peregrine Returns, Mary Hennen gives wings to this extraordinary conservation success story. Drawing on the beautiful watercolors of Field Museum artist-in-residence Peggy Macnamara and photos by Field Museum research assistant Stephanie Ware, as well as her own decades of work with peregrines, Hennen focuses her tale on Illinois's Chicago Peregrine Program, a collaboration between researchers and citizen scientists. She follows the journey of Illinois's peregrines from their devastating decline to the discovery of its cause (a thinning of eggshells caused by a byproduct of DDT), through to recovery, revealing how the urban landscape has played an essential role in enabling falcons to return to the wild and how people are now learning to live in close proximity to these captivating raptors. Both a model for conservation programs across the country and an eye-opening look at the many creatures with which we share our homes, this richly illustrated story of the Chicago Peregrine Program is an inspiring example of how urban architecture can serve not only our cities' human inhabitants, but also their wild ones.