In 1938, Dr. Albert Hofmann (1906-2008) discovered the most potent consciousness-altering substance - LSD. Five years later, he conducted the first intentional self-experiment with the psychedelic. LSD is a substance that has influenced science, culture, and society in the second half of the 20th century more than perhaps any other substance before it. On this occasion, this book gathers its most important texts and lectures from the last two decades. It includes additional contributions from Ralph Metzner, Günter Amendt, Wolf-Dieter Storl, Myron J. Stolaroff, Mathias Bröckers, Christian Rätsch, Claudia Müller-Ebeling, Jonathan Ott, Roger Liggenstorfer, among others. This is a new edition of the 2006 title, marking the 80th anniversary of Albert Hofmann's first LSD self-experiment (Bicycle Day) and the designation of the Greek site of Eleusis as a UNESCO World Heritage Site.