[en] The Dominant-Phase Theory of Microemulsions (DPTM) shows that gels can be transformed into microemulsions by the addition of suitable cosurfactants and indicates the chemical form that these cosurfactants should have. This is possible because, according to the DPTM, the most important factor determining the physical state of the mixture is the stretching force acting on the emulsifier molecules. The DPTM postulates that in a microemulsion this stretching force is small and as a result the emulsifier molecules are subject to little restraint, giving a mixture of low viscosity, whereas in a gel the stretching force is large, resulting in a mixture of high viscosity because the motion of the emulsifier molecules is restricted. For high efficiency counting, the oil and all cosurfactants and emulsifiers in the mixture must contain a benzene ring in their molecular structure. The application of these ideas is illustrated by a description of the development of an emulsion liquid scintillation counting mixture for the high efficiency, high merit value and stable counting of up to 30 percent sodium hydroxide aqueous solutions using toluene as the oil and Triton X-100 as the emulsifier, with 2-phenylethanol and DL-2-hydroxy-2-phenyl acetic acid (mandelic acid) as cosurfactants