8Issam El-Said pinpoints the rules of composition that form the basis of the geometric concepts of Islamic art. He then shows how intricate patterns are based on these basic principles. Fully illustrated in three colors to show the development of the patterns, this book offers an insight into how craftsmen and designers in the Muslim world achieved monumental feats of artistic expression using the simplest of tools. Chapter I presents graphical analyses of numerous complex patterns, to reveal the numerical rationale behind them. In Chapter II, the author analyses the system of measure used in ancient Egypt, before the use of numbers for calculating measurements. He shows how measuring cords and a geometric method based on a grid-pattern originating from the circle were employed by master craftsmen in the design of Islamic art and architecture. The book offers an insight into how craftsmen and designers in the Muslim world have achieved monumental feats of artistic expression with harmony and precision, using the simplest of tools such as a ruler, a string and templates, together with a system of measure that is both simple and sophisticated.