Since antiquity, the Golden Section bas played a significant role in many parts of geometry, architecture, music, art, and philosophy. But it also appears in the newer domains of technology and fractals. In this way, the Golden Section is no isolated phenomenon but rather, in many cases, the first and also the simplest non-trivial example in a sequence of generalizations leading to further developments. It is the purpose of this book, on the one hand, to describe examples of the Golden Section, and on the other, to show some paths to further extensions. This English edition has been prepared, with the authors cooperation, to make it available to English-speaking students of mathematics. The treatment is informal and the text is enriched by the presence of especially illuminating diagrams. Questions are posed at fairly frequent intervals, and the answers to these questions, perhaps only in the form of very broad hints, are gathered together at the end of the book.