One of the most prolific of contemporary sociologists, S. N. Eisenstadt has been an immense stimulus in revitalizing the comparative macro-sociological orientation of the discipline. He has done this through cross-cultural studies and through historical ones, with a fundamental concern for understanding the whys and wherefores of social change. At the core of this concern stands the problem of coming to grips with modernity. Surely, a cluster of basic sociological questions revolves around the quatrain: What is modern? What is unmodern? What is antimodern? What is postmodern? It is not my purpose to go over Eisenstadt's many writings, which inform these core questions from different approaches, but let me note that ten years ago he brought out a major synthesis of his writings in this general vein of sociological inquiry entitled Tradition, Change, and Modernity (1973). His essays in Part 3 of that work ("The Traditions of Modernity") are particularly suggestive in regarding modernity itself as a nontraditional "Great Tradition" (1973:203). In this essay I intend to probe further into modernity as a heuristic concept and, in particular, to raise the question of its spatial locations in the world historical process.