The contents of this essay consist of three parts. The first part stresses the contradictory character of the social world in the XXI century as a single system (in terms of its information technology and market economy) and a fragmented world (in its political and cultural spheres), and identifies global integration and global governance as key problematic questions. The second part addresses these questions from a sociological perspective, updating existing theories and discussing the role of markets, government organizations and communities as institutional mechanisms of social integration and governance of the world system. Finally, in the third part, the author espouses his own notion of democratic global governance and analyses the main factors favoring or hindering peaceful integration and democratic governance at the world level.