Abstract: A foam concentrate comprising from about 7.5% to about 12% by weight of an anionic surfactant, from about 4% to about 9% by weight of an ammonium salt surfactant, from about 1% to about 8% by weight of a nonionic surfactant, up to about 5% by weight of a lipophilic agent, up to about 9% by weight of an alkoxylated ammonium alkyl sulfate and the balance being substantially water or other suitable non-flammable carrier diluent, when diluted with from about 33 to about 99 times its weight of water, is useful for extinguishing fires of Class A combustibles.Those concentrates which contain at least 1% by weight of a lipophilic agent, when diluted similarly, yield foams which are useful for extinguishing Class B fires and mixed Class A and Class B fires. Concentrates containing at least 1% by weight of alkoxylated ammonium alkyl sulfate, when diluted with brackish, saline or hard water, yield foams which extinguish fires. Optimum and preferred ranges for the various components are given.