In 1959, the Dalai Lama fled Lhasa, leaving the People's Republic of China with a crisis on its Tibetan frontier. Sulmaan Wasif Khan tells the story of the PRC's response to that crisis and, in doing so, brings to life an extraordinary cast of characters: Chinese diplomats appalled by sky burials, Guomindang spies working with Tibetans in Nepal, traders carrying salt across the Himalayas, and Tibetan Muslims rioting in Lhasa. What Chinese policymakers confronted in Tibet, Khan argues, was not a 'third world' but a 'fourth world' problem: Beijing was dealing with peoples whose ways were defined by statelessness. As it sought to tighten control over the restive borderlands, Mao's China moved from a lighter hand to a harder, heavier imperial structure. That change triggered long-lasting shifts in Chinese foreign policy.