Various means have been investigated for reducing fuel fire vulnerability of Army combat vehicles by altering fuel compositions. Extensive laboratory studies have yielded clear-to-hazy fire-resistant fuel microemulsions of water in surfactant-stabilized diesel fuel, with and without an antimist agent. The surfactant is a mixture of reaction products of diethanolamine and oleic acid. Flammability and ballistic tests reveal diminished mist flammability with self-extinguishing pool fires, even at temperatures above the base fuel flash point. No difficulties have been encountered in starting, idling, and running unmodified diesel engines on such fuels under typical operating conditions.