The popular image of smoke-filled Chinese opium dens is based on the fact that China was for many decades the leading consumer of narcotics. Vastly profitable for colonial Britain but a detriment for China, the drug trade led to bitter wars and to the creation of a powerful underground international industry. When the business of narcotics went from legal commodity to illicit substance, traffickers needed political connections, and political connections were readily made in China's chaotic environment of civil war and imperial rivalry. Drug traffickers flourished because they were useful to various parties: warlords, professional criminals, Chiang Kaisheks Guomindang, Mao's communists, spies, and Japanese adventurers. This review of the history of drug trafficking concludes that drug traffickers are entrepreneurs, who have sought out profitable drug markets and attempted to deal with impediments to their business operations. Generally, drug trafficking has flourished in times and places of political instability, where politicians needed money, intelligence, and other resources that traffickers could offer. These alliances were often productive in the short term, but they rarely lasted. Both drug traffickers and their political allies were consummate opportunists, and opportunities appeared or disappeared with changing circumstances. As long as there is a demand for drugs and the drugs in demand are illegal, traffickers will seek out and establish alliances with politicians. These alliances are not conspiracies, but are the political economy of the international narcotics traffic. Chapter notes, a 160-item bibliography, and a subject index