This book presents a modern approach to space-time physics. It details a comparative analysis of the Lorentz Transformations of Special Relativity, the accepted theory of space and time, and space-time transformations involving an Absolute Space developed by Italian physicist Franco Selleri. The foundation of this work is Selleri’s ground-breaking contributions in space-time physics and makes the case that the observation-based Selleri Transformations are in better accord with the physical world than the postulate-based Lorentz Transformations which produce many “paradoxes.” The book describes an approach to space-time physics using the Selleri transformations that accurately accounts for the full range of relativistic phenomena and associated experiments from time dilation, transverse Doppler effect and relativistic beaming to the Michelson-Gale experiment, GPS clock synchronization and Thomas precession, all without paradoxes. The Lorentz transformations cannot make this claim, despite their universal acceptance. For example, one would be hard-pressed to find in any special relativity textbook, treatment of the century-old Michelson-Gale experiment, analysis of critically important GPS ground-clock synchronization, or explanation of the 2004 Wang experiment involving light propagation in a moving optical medium, all of which are fully treated in the book using the Selleri transformations. This book therefore represents a serious contribution to the literature on space-time physics. It addresses questions unanswered by special relativity and promotes the development and application of the subject in a logically consistent and coherent manner. After more than a century of criticisms of special relativity theory, there finally is resolution of issues using the Selleri transformations. An intellectual adventure awaits the curious reader.