This book was motivated by the desire we and others have had to further the evolution of the core course in field propulsion science and technology for space flight. This book covers fundamentals of quantum field theory and its application to space propulsion science and it also mentions other field propulsion methods utilizing Einstein's relativity theory and other interesting theories. This book surveys some areas of the subject that have been particularly productive in theoretical terms, but also dedicate attention to subjects that may be of more immediate practical interest. The authors cover the foundation of the field propulsion theory to envision alternative processes, but they also make a field theory approach to be prepared to tackle the role of fields in the great design of advanced and innovative propulsion processes for the future of space flight.