This chapter is devoted to another important property of surfactants,
that of stabilization of water-oil films and formation of microemulsions. These
are a special kind of colloidal dispersion that have attracted a great deal of
attention because of their ability to solubilise otherwise insoluble materials.
Industrial applications of microemulsions have escalated in the last 40 years
following an increased understanding of formation, stability and the role of
surfactant molecular architecture. This chapter reviews main theoretical
features relevant to the present work and some common techniques used to
characterize microemulsion phases.