During the proposed seminar we will examine the structural aspects of the history of architectural development and try to describe the ways forward. We will participate in the discussion on sustainability in architecture, which often focuses on the lifespan of building infrastructure. Eternal, temporary and changeable buildings will be the topic. We will try to understand how the development and introduction of new building materials shape cities, architecture and lifestyles. The main part of the seminar will be an excursion to Warsaw. The city, almost wiped off the map during the Second World War, has undergone enormous development in the last 30 years. It is an example of dreams and limits, good and bad trends, and official and unofficial building policies.