Scientific progress has always been driven by strong personalities and the experiments, discoveries, theories and inventions of great scientists have revolutionized the ways we understand the world and the way we live. Think of gravity, evolution, relativity, radioactivity, the genetic code and the Big Bang; electric motors, nuclear power, synthetic drugs, brain scanning, computers and the internet. This book tells the remarkable lives of the pioneers - from Galileo and Newton, Faraday and Darwin, Pasteur and Marie Curie, to Einstein, Freud, Turing and Crick and Watson. Often unorthodox thinkers, these scientists frequently had to struggle to gain recognition for their work, in order to leave their legacy to future generations. Written by an international team of distinguished scientists, historians of science and science writers, the book covers all of the major scientific disciplines, from astronomy to psychology. It begins at the largest scale with the 'Universe', and moves to progressively smaller scales through the 'Earth' and 'Molecules and Matter' to 'Inside the Atom'. The last two sections look at the phenomena of 'Life' and 'Body and Mind'. Each of the forty-three outstanding individuals is portrayed in engravings, paintings, photographs and sculptures. In addition, the book reproduces many of their own notes, drawings and diagrams, along with their letters that allow a more intimate view into their journeys of discovery.