Tokyo is characterized by its fluid urban fabric. This paper explores the determining structures, processes, and changes, drawing on the historical development of modern Tokyo as well as voices of the city planner community in the advent of the 2020 Tokyo Olympics. The study shows that Tokyo’s urban structure is not finalized but contested, not static but changing. Large-scale corporate development and human-scale heterogeneity are prevalent contemporary urban forms, but only two of several possible dominant patterns in the future. “Whose city is Tokyo?” is therefore also the crucial question regarding the legacy of the Olympic Games.