Chang's 2005 work, a biography of Mao, was co-authored with her husband Jon Halliday and portrays Mao in an extremely negative light. The couple traveled all over the world to research the book, which took 12 years to write. They interviewed hundreds of people who had known Mao, including George H. W. Bush, Henry Kissinger, and Tenzin Gyatso, the Dalai Lama. Kissinger called it "grotesque in that it depicts Mao as a man without any qualities." Later, he described it in his book "On China" as "one-sided but often thought-provoking."