In Vienna after WWI and Berlin after WWII, the provision of mass housing not only was a response to a dire social need but also served as a key lever for building variants of socialism and liberalism. Zooming into the interplay between political ideologies and the production of space, this book shows that ideologies, understood as political beliefs that underpin everyday life, are never simply 'written' into space but that their meaning is made and re-made, negotiated and contested, and sometimes cunningly subverted in and through space. How people live was - and continues to be - a profoundly political question that involves negotiations of, and decisions on, norms and ideals of citizenship, freedom, equality, property, democracy, gender, and family life - negotiations and decisions that come with legacies that shape the present.