The vision of modern urban planning after World War 2 was a remarkably standardized project around the world. Implementation was also universally problematic, the heady reformism of 1940s reconstructionism never being comprehensively realized. Moreover, by the 1970s the early 'heroic' modernism had evolved into a counterrevolutionary 'high' modernism. Exemplifying these themes was the career of the Sydney-based architect-planner Waiter Punning (1912-1977). In this paper I provide an overview of his particular brand of modernist thought, his central planning ideas, and his physical planning work, with special reference to a disastrous redevelopment scheme near the end of his life. The nature and scope of Walter Punning's professional life represent a virtual microcosm of the uneven course of planning in Australia in the postwar years: genesis in the avant-garde Le Corbusier-tinged modernism of the 1930s, the early priorities, the broadening agenda but ever moderating tone, the difficulties in translating heady dreams into reality, and the crises which led to the emergence of a new paradigm. I will demonstrate how a biographical approach to planning history can illuminate the origins, meanings, hopes, and outcomes of modernist planning in the urban arena.