In this book professor Lubin lays out the fundamental physics and mathematics required to radically alter our capabilities in propulsion to enable extremely high speed space flight both in our solar system and beyond. The case is made that the only currently viable solution to enable this transformation including relativistic flight for the first interstellar robotic missions is using large scale directed energy. Traditional methods of propulsion are not capable of achieving the speed required for rapid missions in our solar system, including fast crewed missions to Mars as well as the many robotic missions desired both in our solar system and to the nearest stars. Humanity has now reached a technological tipping point with the ability to project power over vast distances with transformational implications in a wide variety of areas from propulsion to beaming power throughout our solar system to planetary defence. In a series of over 50 technical papers the fundamentals of this transformation are outlined and synthesized in this book allowing a detailed understanding of the many challenges ahead and a roadmap to the future direction for human exploration far beyond our solar system. While the road ahead is long and challenging it provides the path to radically altering humanity's future in ultra high speed space exploration.