With around 30 million migrants worldwide, the ethnic Chinese and the Chinese in diaspora form the largest diaspora in the world. The economic reform of China in the late 1970s marked a huge phase of migration from China, and the new migrants have had a major impact on the local societies (including the ethnic Chinese) and on China. The transnational networks between the Chinese in diaspora and China have become even more significant as China has emerged as an economic world power. Most of those who migrated in the 19th and 20th centuries have largely become citizens of the respective countries; these may be referred to as ethnic Chinese, in contrast to those who remain citizens of China as well as new migrants from the country. This will be an important reference work for students, scholars and policy makers worldwide, given the global distribution of the Chinese and the emergence of China as a world power, both economically and politically.