A sequence of conflicts and crises shaking international system in the last few years has clearly demonstrated inconsistency in many ideas and concepts which gained prominence in the Western international studies in the first two decades after the end of the Cold War, and has initiated a process of their critical reassessment. This paper focuses on one of such concepts — the concept of ‘security–development nexus’. To date this concept has become firmly engrained in the official discourse of the leading donors and has been consistently reiterated in the Western studies of the Global South. However, until recently it has not been the subject to a thorough examination in the Russian political science. The present paper outlines the key theoretical and methodological difficulties pertaining to conceptualization of the ‘nexus’, identification of its specific characteristics, and its application to studying and addressing the challenges of the Global South. The first section provides a general description of contemporary debates in the Western academic and expert community over the concept of ‘security–development nexus’, and identifies several deficiencies in the use of the concept by major bilateral and multilateral donors. The author emphasizes that some scholars go beyond mere criticism and seek to remedy these deficiencies and provide a more solid theoretical foundation for empirical studies of the nexus. The second section examines the scholarly works that focus on the theoretical aspects of the nexus, its denotation and structure and identifies their strengths and weaknesses. The author comes to the conclusion that at present the most promising direction for further study of the ‘nexus’ consists in tracking the emergence and evolution of its constitutive notions, i.e. security and development, and embedding the ‘nexus’ within corresponding discourses.