PART 1 DISPUTES WITH EINSTEIN: Einstein and Nordstrom - Some Lesser Known Thought Experiments in Gravitation, John D. Norton; Out of the Labyrinth? Einstein, Hertz, and the Gottingen Answer to the Hole Argument, Don Howard and John Norton; Conservation Laws and Gravitational Waves in General Relativity (1915-1918), Carlo Cattani and Michelangelo De Maria; The General Relativistic Two-Body Problem and the Einstein-Silberstein Controversy, Peter Havas. PART 2 THE EMPIRICAL BASIS OF GENERAL RELATIVITY: Einstein's Explanation of the Motion of Mercury's Perihelion, John Eannan and Michel Janssen; Pieter Zeeman's Experiments on the Equality of Inertial and Gravitational Mass, A. J. Kox. PART 3 VARIATIONAL PRINCIPLES IN GENERAL RELATIVITY: Variational Derivations of Einstein's Equations, S. Kichenassamy; Levi-Civita's Influence on Palatini's Contribution to General Relativity, Carlo Cattani. PART 4 THE RECEPTION AND DEVELOPMENT OF GENERAL RELATIVITY: The American Contribution the the Theory of Differential Invariants, Katin Reich; The Reaction to Relativity Theory in Germany III - Hundred Authors Against Einstein, Hubert Goenner; Attempts at Unified Field Theories (1919-1955). Alleged Failure and Intrinsic Validation/Refutation Criteria, Silvio Bergia; Vladimir Fock - Philosophy of Gravity and Gravity of Philosophy, Gennady Gorelik; S. Chandrasekhar's Contributions to General Relativity, Kameshwar C. Wali. PART 5 COSMOLOGY AND GENERAL RELATIVITY: Lemaitre and the Schwarzschild Solution, Jean Eisenstaedt; E. A. Milne and the Origins of Modern Cosmology - An Essential Presence, John Urani and George Gale.