This book addresses all scientists and others interested in the origins, development and fate of intelligent species in the observable part of our universe. In particular, the author scrutinizes what kind of information about extraterrestrial intelligent life can be inferred from our own biological, cultural and scientific evolution and the likely future of mankind. The first part of the book provides the necessary background information from space and life sciences, thus making the book also accessible to students and the scientifically educated public. In this second edition of Peter Ulmschneiders successful and highly interesting book the author is putting even stronger emphasis on the geological conditions and consequences of lifes conquest of land as the pre-condition for the emergence of life with our type of technical intelligence.