Astronomer Peter Linde takes the reader through the story of the search for extraterrestrial life in a captivating and thought-provoking way, specifically addressing the new research that is currently devoted towards discovering other planets with life. He discusses the methods used to detect possible signals from other civilizations and the ways that the space sciences are changing as a result of this new field. “Are we alone?� is a mystery that has forever fascinated mankind, gaining momentum by scientists since the 1995 discovery of the existence of exoplanets began to inspire new ways of thinking in astronomy. Here, Linde tries to answer many philosophical questions that derive from this area of research: Is humanity facing a change of paradigm, that we are not unique as intelligent beings? Is it possible to communicate with others out there, and even if we can—should we?