The theoretical method of “A Journey to the Stars” is treated in this book. The distance to a stellar system is too huge, therefore the travel to the fixed star nearest to the Earth using the present propulsion technology will require tens of thousands years. In order to overcome such a limit of the space travel between fixed stars, research and development of a new propulsion theory and navigation theory are indispensable. As a promising approach, space drive propulsion theory and Hyper-Space navigation theory given by a space-time featuring an imaginary time (i.e., Time-Hole) are introduced. Space drive propulsion system is one of field propulsion system utilizing the action of the medium of strained or deformed field of space. The curvature of space plays a significant role for the propulsion theory. On the other hand, a plunging into Hyper-Space characterized by imaginary time would make the interstellar travel possible in a short time. The Hyper-Space navigation theory would allow a starship to start at any time and from any place for an interstellar travel to the farthest star systems, the whole mission time being within human lifetime.