Before moving to Brooklyn, New York, Chaim Jones didn't know what a feral cat was. But when he encountered a colony of unowned cats living in the neighborhood's backyards, his life began to change. In Fence Crossers, Jones tells the story of how he came to admire and love these beautiful, enigmatic animals, and describes the cats' individual personalities and social dynamics. He explains trap-neuter-return (TNR), the rational and humane way to care for them, and relates his experiences practicing it. A birdwatcher, Jones analyzes and critiques the opposition to TNR from birding organizations and other conservationists. And he considers caring for feral cats in a broader social context, and shares some thoughts about how we can better help them, and the people with whom they live.