The creation of the Canadian Light Source (CLS) in Saskatoon, which began operation in 2004, was the largest science project in Canada in the last fifty years. The multi-beam facility operates more than five thousand hours per year and has more than one thousand Canadian and international users from a wide range of science, medical, and engineering disciplines. This book describes the decades of intense research from many scientists to justify this project and the resulting outstanding research covering many areas of the physical, biological, medical, and agricultural sciences. With personal accounts and frank narration, this book describes the long history leading to the CLS, beginning in Saskatoon in the 1930s. The core of the book highlights the remarkable and unselfish collaboration and cooperation of a few hundred people from Canadian and international universities, governments, and industry, showcasing how the Canadian Light Source represents pure and applied research at its finest.