Windows - those thinner patches in the external skins of buildings that function as both barrier and channel between the individual and the outside world. They structure the facades of buildings and hence our everyday environment. They display articles of desire, technological progress and economic growth and so reveal new departures in style, aspiration and attitudes to the individual. Through the built environment in which we live, windows even function as building blocks of our personal identity. This volume illustrates how an item so central to our everyday life comes to govern aesthetic discourses concerned with openness and knowledge. It also identifies how, in the German cultural context, the literature, art and architecture of different epochs exploit the window's potential as both physical portal and metaphor for human interconnectedness, self-perception and the transcendence of the self.