This book describes at the introductory level how modern technology has made the scenario of the classic science-fiction movie Fantastic Voyage a reality. The movie is about a submarine and its crew members being shrunk to microscopic size and ventured into the body. Exactly 50 years following the release of the film, such reality takes the form of a medical interventional room capable of mimicking this scenario. Based on 15 years of intensive research and development by the world-leading team in this specific field, the book goes through the scenes of the movie while explaining how it is implemented in this first-of-a-kind interventional facility.This is the first book that explains the fundamentals of navigation of therapeutic agents in the vascular network. The scope of the book is twofold: (1) to initiate readers into various technologies, including, but not limited to, nanotechnology, robotics, and biochemistry (more importantly, it shows how critical the integration of all these disciplines is to solving problems that indeed require a multidisciplinary environment); (2) to inspire the younger generation by showing that science and technology can bring one everywhere with the power to transform fiction to reality that can help humankind.