This chapter reviews the history of corporatist welfare regimes and focuses on the relationship between the welfare regime and its economic system. Collective bargaining in businesses is the most fundamental prerequisite of tripartite cooperation in the modern welfare system. The chapter explores China's Trade Union Law Amendment, in which, for the first time, legislation has defined the legal role and status of trade unions in "collective bargaining". The welfare state systems of developed countries, established after World War II, were based on cooperation among three parties—the employees' organization, the employers' organization, and the state. The choice and formulation of a social security system essentially means that the choice and formulation of a corresponding economic system in a sense embodies the nature of a country's social economic system. The corporatist factor, or the degree of cooperation among the tripartite partnership, is a question of size, not of existence, in the economic and welfare systems of any developed country today.