Flammable liquids are in widespread use throughout the chemical industries, as well as other sectors of society. Knowledge of the flash points, or the temperature at which vapors above a liquid will propagate a flame, is of vital importance for process safety. While the flash points of many liquids are well known, that for mixtures is not well known; however, it is known that some mixtures exhibit flash points very different from those of the pure components. This work examines some of the factors affecting the flash point for binary mixtures, including chemical structure, composition, and deviation from ideal vapor liquid equilibrium behavior, for various types of mixtures.