Apart from some incidence in the early twentieth century, modern-style business groups emerged in China in the mid-1980s as a consequence of the reform and restructuring of state-owned enterprises, which aimed at increasing economies of scale and specialization. Since their early emergence, a substantial number of Chinese business groups have succeeded in becoming major players in the world economy, and the Chinese government has played an important role in the formation and development of these business groups. This article provides a descriptive analysis of the business groups in China, extending and updating the recent literature. It discusses a basic profile and history of these business groups. It also focuses on the role of the state in the emergence of these groups. Finally, it discusses the problems of ownership structure and agency costs in these business groups, and deals with their business structure and diversification.