This lecture by the instructor explores the potential of existing buildings through 6 current projects in various Swiss cities, emphasizing the architectural attitudes 'Re-Use, Reduce, and Revaluate'. By showcasing recent examples of building transformations and redevelopments, the lecture highlights the importance of recognizing and utilizing the existing structures to reduce greenhouse gas emissions, construction costs, and resource consumption. The presentation also delves into the social, economic, and environmental benefits that come with repurposing buildings, ultimately aiming to create sustainable and socially valuable spaces for post-carbon society.