The performance of individual international organizations (IOs) has received considerable scholarly attention, not in the least because their importance for global governance. This paper adds to this body of work by adopting genuine comparative lenses. Based on a novel survey, it assesses the attributed performance of 49 IOs over two important dimensions: problem-solving effectiveness and legitimacy of outputs. This reveals variation between IOs with respect to both components. We derive hypotheses from international cooperation and IO design. The quantitative analysis reveals that except deliberative diplomatic practices many factors increasing attributed legitimacy differ from the ones increasing the attributed problem-solving effectiveness. Most notably, autonomous secretariats increase the problem-solving effectiveness attributed to IOs. Legitimacy attributions increase when IOs are regional instead of global in nature and when non-state actors have access to IO decision-making.

个别国际组织 (IO) 的表现受到了相当多的学术关注，至少因为它们对全球治理的重要性。本文通过采用真正的比较镜头增加了这项工作。根据一项新颖的调查，它评估了 49 个 IO 在两个重要方面的归因绩效：解决问题的有效性和产出的合法性。这揭示了 IO 之间关于这两个组件的差异。我们从国际合作和 IO 设计中得出假设。定量分析表明，除了慎重的外交实践之外，许多增加归因合法性的因素与增加归因解决问题有效性的因素不同。最值得注意的是，自治秘书处提高了 IO 解决问题的效率。