SMEDDS (Type III B systems) are isotropic mixtures of oils, surfactants, co-solvents and co-surfactants that have the capability to create fine o/w microemulsions upon mild stirring followed by dilution in the aqueous phase. They have captured due attention because of their high transparency, high solubilization capacity, thermodynamic stability and simple production method. They also improve oral assimilation and eradicate food effects. There has been an upheaval over the most recent two decades in the usage of microemulsion systems in an assortment of pharmaceutical, chemical and industrial processes. The use of self-microemulsion in pharmaceuticals, as cosmetics agents, for analytical purposes, in biotechnology, as enzymatic reactions, for immobilization of protein, bioseparations and chemical sensor have been described briefly. Oral, topical, parenteral, oculars and pulmonary deliveries are the general routes of drug administration for LBDDS that are discussed in detail. The oral route includes SE capsule, SE sustained/controlled release tablet/capsule/ pellets, SE solid dispersions. This chapter highlights various benefits, drawbacks, selection of ingredients and the applications of self-emulsification in various fields such as cosmetics, analysis, bioseparation and so on.