The private house has perhaps always been a prototype for more elaborate architecture, but never more so than in the heyday of the Modern Movement, when it provided both the opportunity for experiment and the chance to explore creatively the changing essence of dwelling. This article, based on a keynote lecture given to the Alvar Aalto Foundation in February 2015, compares the generating principles of Alvar and Aino Aalto's own house of 1936 with those of built and unbuilt houses by Hugo Häring, underlining the importance of specific planning and spatial relationships as the essential generators, to which the making of façades remained subordinate or at least secondary. Häring's Woythaler House of 1927 also appears here for the first time in a properly comprehensible form, thanks to information recovered from drawings now available in the public realm.