Historical and Philosophical Aspects.- Isotropy of Inertia: A Sensitive Early Experimental Test.- The Challenge of Practice: Einstein, Technological Development and Conceptual Innovation.- Foundation and Formalism.- Foundations of Special Relativity Theory.- Algebraic and Geometric Structures in Special Relativity.- Quantum Theory in Accelerated Frames of Reference.- Vacuum Fluctuations, Geometric Modular Action and Relativistic Quantum Information Theory.- Spacetime Metric from Local and Linear Electrodynamics: A New Axiomatic Scheme.- Violations of Lorentz Invariance?.- Overview of the Standard Model Extension: Implications and Phenomenology of Lorentz Violation.- Anything Beyond Special Relativity?.- Doubly Special Relativity as a Limit of Gravity.- Corrections to Flat-Space Particle Dynamics Arising from Space Granularity.- Experimental Search.- Test Theories for Lorentz Invariance.- Test of Lorentz Invariance Using a Continuously Rotating Optical Resonator.- A Precision Test of the Isotropy of the Speed of Light Using Rotating Cryogenic Optical Cavities.- Rotating Resonator-Oscillator Experiments to Test Lorentz Invariance in Electrodynamics.- Recent Experimental Tests of Special Relativity.- Experimental Test of Time Dilation by Laser Spectroscopy on Fast Ion Beams.- Tests of Lorentz Symmetry in the Spin-Coupling Sector.- Do Evanescent Modes Violate Relativistic Causality?.