Panda breeding has been highlighted as one of the big success stories in conservation: U.S. and Chinese scientists working together to increase the number of pandas released into the wild. But a New York Times investigation found that they have succeeded only at making more pandas for zoos. Individual pandas have been hurt in the process, and at least one has been killed. Mara Hvistendahl, an investigative reporter for The Times focused on Asia, explains how records, photographs and videos — many of them from the Smithsonian Institution Archives — offer the most detailed, unvarnished history of the program.