The article explores the phenomenon of the subjective right of an individual to renounce the citizenship of one state and acquire the citizenship of another state. Taking into account the transformation of the geopolitical situation and political systems of modern states, the issues of renouncing citizenship and acquiring citizenship are being updated in the general concept of development of the institution of citizenship. The study, based on scientific methods, presents the concept of protecting human rights at the level of international and national law, focusing on the tendency to increase the influence of international law on the content of citizenship and on the protection of human rights. An analysis of the historical retrospective of the legal regulation of international and domestic practice in the development of the institution of citizenship has been carried out, and the conceptualization of the main definitions of citizenship relations has been substantiated. A review of scientific literature and regulatory legal acts at all levels made it possible to identify patterns in the development of issues of acquiring citizenship and renouncing citizenship.