The potential of inorganic compounds and their mixtures is receiving consideration from various practical viewpoints, for example, the relatively large latent enthalpies that accompany the process of melting have directed consideration of such materials in the design of a series of 'second-generation' thermal energy storage subsystems of considerably greater capacity than the systems utilizing the storage capacity of fluids (such as water) and rocks. As molten salts, the features of large liquid state ranges, low vapor pressures, high electrical conductivities, and good viscosities are important considerations relative to diverse applications, such as heat transfer fluids, solvents, reaction media, and as molten electrolytes. The present compilation provides an authoritative compendium of melting points, and compositions of molten salt eutectic mixtures. Data for mixtures melting in the range - 138C to 2800C are reported. Value judgments have not been attempted. Titles of the articles in the literature citations and a system index are included for approximately 6000 eutectic entries.