The author discusses different approaches to the study of international institutions: realism, neofunctionalism, liberal institutionalism, — giving attention to the more considerable works by scholars active in the study of international relations. Investigating the hierarchy and structure of international institutions within the framework of the above mentioned research approaches, M.V.Safonov dwells on the specific characteristics of the “Big Eight” club’s activities. Although different authors differently evaluate the character and the status of the club, its role in world politics enables its being considered a full value international institution, the author maintains.