Recent decades have seen an intensification of international organizations’ (IOs) attempts to justify their authority. The existing research suggests that IO representatives have scaled up self-legitimation to defend their organizations’ legitimacy in light of public criticism. In contrast, this article demonstrates that IOs intensify self-legitimation to mobilize additional support from relevant audiences when their authority increases. We argue that self-legitimation aims primarily to achieve proactive legitimacy expansion instead of reactive legitimacy protection. We develop this argument in three steps. First, we draw on organizational sociology and management studies to theorize the connection between self-legitimation and an organization’s life stages. Second, we introduce a novel dataset on the self-legitimation of 28 regional IOs between 1980 and 2019 and show that the intensity of self-legitimation evolves in phases. Third, we provide a multivariate statistical analysis and a brief vignette on the African Union, both of which indicate that IOs that shift from unanimity or consensus to majority voting tend to intensify self-legitimation.

近几十年来，国际组织（IO）加强了证明其权威的努力。现有的研究表明，面对公众的批评，IO 代表已经扩大了自我合法性，以捍卫其组织的合法性。相比之下，本文表明，当国际组织的权威增加时，它们会加强自我合法化，以动员相关受众的额外支持。我们认为，自我合法化的主要目的是实现主动的合法性扩张，而不是被动的合法性保护。我们分三步阐述这一论点。首先，我们利用组织社会学和管理研究来理论化自我合法化与组织生命阶段之间的联系。第二，我们引入了一个关于 1980 年至 2019 年间 28 个地区 IO 自我合法化的新颖数据集，并表明自我合法化的强度是分阶段演变的。第三，我们提供了关于非洲联盟的多元统计分析和简要介绍，两者都表明，从一致同意或共识转向多数投票的国际组织往往会强化自我合法化。