Abstract: Differentiated integration has become a trendy topic in the European integration research. Based on a review of the existing research, this paper finds that after its emergence in the 1980s, the research of differentiated integration has attracted increasing research attention and boomed in recent years. The rise of this research has its roots in the historical and academic contexts of European integration, namely the gradual institutionalization of differentiated integration in the European Union laws, the constant increase of the practice of such policies, and the insufficiency of traditional theories in explaining new issues in European integration. The differentiated integration research has brought a shift of approach in the European integration research, and introduced new research topics concerning the integration process in dynamic development. However, as an emerging research field, the differentiated integration research is still in its early days, which is manifested in the divergence among scholars in defining core concepts, and the relative inadequacy of theoretical research.

Key words: differentiated integration, European Union, European integration research

摘要： 差异性一体化研究已经成为欧洲一体化研究的一个热门课题。本文通过梳理国外已有的研究成果，发现差异性一体化研究始于20世纪80年代，此后相关研究逐渐增加并在近年步入兴盛。差异性一体化研究的兴起有着深刻的历史背景与学理背景，即差异性一体化在欧盟法律中逐渐制度化；差异性一体化政策实践不断增加；传统欧洲一体化理论对一体化中新问题的解释力不足。差异性一体化研究带来了欧洲一体化研究思路的转变，并为处于动态发展中的一体化进程提出了新的研究议题。然而，差异性一体化研究作为一个新兴研究领域，仍然处于发展完善阶段，表现为学术界对核心概念的界定存在分歧以及理论研究相对滞后。

关键词: 差异性一体化, 欧盟, 欧洲一体化研究