Bernard A. Lietaer (1942 - 2019) was active worldwide as a financial expert. He advised companies, governments and NGOs. In addition, he presented his ideas and concepts to a broad public in numerous books, essays and interviews. He also taught at various international universities. After his success as a senior executive of the Belgian Central Bank and as manager of a hedge fund, he increased his commitment to complementary currencies and currency systems. In this field, he is considered a key innovator, particularly since the 1980s, and is considered to be one of the key innovators in the field, especially since the crypto-currencies of today. This book (Volume I), Translation of the original German edition by Elisa Graf and supplemented with a foreword by Sally Goerner, is the first to provide a detailed overview of Lietaer's life and work. Lietaer authorized the author for this work shortly before his death. It vividly describes the contexts in which Lietaer developed and represented his ideas. By describing Lietaer's spiritual background for the first time, his work can be seen in another important context. (Volume II: Numerous color illustrations to Volume I, facsimiles and previously unpublished texts by Lietaer, as well as supplementary reflections).