The book extends Special Relativity to include (Superluminal) transformations to reference frames moving at relative velocities greater than the speed of light. Tachyons are shown to exist within Black Holes. Tachyons of any spin can be defined and second quantized. Further considerations lead to the ElectroWeak Theory for one generation of leptons and quarks. Thus the general form of ElectroWeak theory, including a rationale for the form of parity violation, SU(2) x U(1), and left-handed doublets and right-handed singlets, is derived.