The scant number of drawings and the absence of any theoretical treatises on the architecture of the pre-Islamic world make the late fifteenth-century Timurid pattern scroll in the Topkapi Palace Museum Library an exceedingly valuable source of information. In the course of her analysis of the scroll, Necipoglu throws new light on the conceptualization, recording, and transmission of architectural design in the Islamic world between the tenth and sixteenth centuries. Her comparison of the Islamic understanding of geometry with that found in medieval Western art makes this book particularly valuable for all historians and critics of architecture. The text also has far-reaching implications for recent discussions on vision, subjectivity, and the semiotics of abstract representation. The book reproduces the entire scroll, with its 114 individual geometric patterns for wall surfaces and vaulting, along with illustrations showing the underlying geometries from which the individual patterns are generated. An essay by Mohahhad al-Asad discusses the geometry of the mugarnas and demonstrates how one of the scroll's patterns could be used to design a three-dimensional vault.