On September 11, 2001, Elizabeth A. Phelps stepped outside her apartment in lower Manhattan and noticed a man staring toward the World Trade Center, about two miles away. Looking up, “I just saw this big, burning hole,” Phelps recalls. The man told her that he had just seen a large airplane crash into one of the skyscrapers. Thinking it was a horrible accident, Phelps started walking to work, a few blocks away, for a 9 A.M. telephone meeting. By the time she reached her eighth-floor office at New York University, a second jet had struck the other tower, which collapsed after an hour. Later, she saw the remaining tower fall.