Abstract
From the 1910s to the 1920s Yasushi Kataoka, Hajime Seki and Hiroshi Ikeda, citing foreign examples, discussed housing problems and urban planning in Japan. Shun-Ichi Watanabe conjectured that urban planners in Europe, the USA and Japan advocated the "Unification" Thesis that urban problems and housing problems should be solved in an integrated way. This paper verifies the hypotheses and reaches the following conclusions: (1) German planners discussed city extension problems and housing issues in an unified way, while British town planners focused upon the amenity of the surroundings of the house, and American city planners excluded housing problems from planning issues; (2) Kataoka, Seki and Ikeda discussed both topics in an dualistic way and tried to enact the Housing Act separately from the Urban Planning Act.
