Sigfried Giedion's small, but vocal manifesto Befreites Wohnen (1929) is an early manifestation of modernist housing ideology and as such key to the broader understanding of the ambitions of the International Congresses of Modern Architecture (CIAM) and the debate on the industrialization of construction processes and its impact on public housing at the beginning of the twentieth century. more An important step in Giedion's rise as one of the foremost propagators of modern architecture, this manifesto is based on the argumentative power of visual comparisons, and the only book the art historian both authored and designed.