Architectural theory has a relationship to the building similar to that of a framework to an arch. It remains invisible; only a careful examination of the finished construction allows for its conceptual reconstruction - this is the task the author of this volume sets for himself. The essays are grouped around three major themes: architectural theory, the architectural history of Central Europe in the 20th century, and architectural criticism. For Ákos Moravánszky, the sensuality of the material carries a significance that goes far beyond its physical properties. He is interested in the tension between abstract theory and concrete optical perception, which is always also related to the effect of the materials, a fascination that is transmitted to the reader. The author also dedicates attention to Central European architecture, which is a second focus of research.