The third volume of the series, Open Living Structures, revisits the ideas of the Polish architect Oskar Hansen (1922-2005) on “open forms,” or architectural forms that allow for completion through the user. At the 1959 CIAM in Otterlo, Hansen questioned the modernist practice of providing social housing through standardized models, instead he called for incomplete systems and for architecture as living structures. Updating this concept for the modern age, this books looks at eight historical and contemporary case studies from Japan and analyzes how they make use of flexible floor plans that can be reconfigured by their residents themselves. What lessons does this performative dimension of architecture prevalent in Japan have for the modern Western architect? The answer is explored in a series of practical applications, in which principles derived from the Japanese case studies are translated into a series of interventions for sites in Berlin.