Diane Vaughan's study of the 1986 space shuttle Challenger disaster overturns the common explanation that NASA managers, pressed by schedules, knowingly broke the rules and gambled with the crew's lives. After nearly a decade spent working through NASA and Morton Thiokol documents, interview transcripts and engineering records, Vaughan, a sociologist, concluded that the fatal decision came from people following the rules, not breaking them. The book's central concept is the "normalization of deviance." Starting in the early 1980s, engineers repeatedly found erosion and hot-gas blow-by on the solid rocket boosters' O-ring seals. Each time, through formal and well-documented procedures, they reclassified the anomaly as an acceptable risk. Because flights kept returning safely, every new deviation became evidence that the joint was safe enough, and the boundary of acceptable risk kept moving.
Vaughan reconstructs, almost hour by hour, the teleconference on the eve of the launch, when Thiokol engineers raised concerns about the unusually cold temperature and were overruled. She shows how the outcome was shaped by an engineering culture that required quantitative proof before it would act, a "culture of production" under budget and political pressure, and "structural secrecy," meaning the way organizational layers and specialized language filtered out warning signals. Her argument is that disaster was produced by ordinary, well-intentioned people inside a system whose structure made a mistake almost inevitable. Her analysis proved painfully predictive when the shuttle Columbia was lost in 2003, and she later worked with the board investigating that accident. The book has become a foundational text in the study of organizational failure, read in fields from engineering and medicine to finance.