Editor's Note: This is the first part of a three-part series on China's household registration system and its effects on the country's labor force and economy. Part 1 explains the origin of the system; Part 2 will discuss the role of the system during the Mao era and after China's economic opening; and Part 3 will examine how the Communist Party of China will use the system to support its push for inland development. China's household registration system, known as hukou in Chinese, is central to the country's statecraft and political history. From the earliest unified dynasties to the Communist Party today, China's rulers have relied on various forms of household registration to reinforce the state's role in shaping the political, social and economic lives of ordinary citizens.