Triad, name for various secret societies in Qing-dynasty China (and sometimes earlier), for modern Chinese crime gangs, and for crime gangs of other Asian nationals operating in their own countries or abroad. A secret society with the name Triad started operating in the early 19th century in southern China, where it took root and spread. In the 1850s Triad rebellions threatened Shanghai and Xiamen (Amoy) and contributed to the revolution of 1911. Chinese secret societies have in common the swearing of an oath to join, strict rules, a family relationship among members, the duty of mutual help, a hierarchy of functions, and hereditary membership within families. In the 21st century, Chinese Triads operate Mafia-like organized crime syndicates internationally, dealing in extortion, prostitution, illegal gambling, and the drug trade. In Italy, Triads have operated in association with the Camorra, one of the country’s largest and oldest criminal organizations.