The paper will explore the significance of the role cities play in transnational institutional bypass of nation-States. The authors provide examples of cities playing the role of a transnational institutional bypass of nation-States and indicate the circumstances that may compel cities to act as such a bypass and fulfil the nation-State functions. The aim of the paper is to show that cities may successfully bypass nation-States in specific circumstances, including some cases of nation-States being unwilling to act in order to achieve a greater good that is in the interests of people living in a given nation-State or, even on a broader scale, in the interests of mankind. To best of the authors’ knowledge, this is the first attempt to introduce the concept of an institutional bypass to cities and to construe conditions applicable in such a case.