Recent progress in combinatorial drug has led to the generation of a large number of new compounds. microemulsions are versatile systems of great technological and scientific interest to the researchers because of their potential to incorporate a wide range of drug molecules (hydrophilic and hydrophobic) due to the presence of both lipophilic and hydrophilic domains. A micro emulsion is a transparent, thermodynamically stable mixture of two immiscible liquid stabilized by surfactant (or mixture of surfactant). Microemulsions have many advantages for instance, more drug solubility, thermodynamic stability, manufacturing and permeation is easy over conventional formulations that convert them to important drug delivery systems. The design and development of microemulsions aimed at controlling or improving required bioavailability levels of therapeutic agents. Through this review an attempt has been made to focus on several recent developments occurred in the field of microemulsions based applications and which confirms its role as a suitable cargoes for delivery of drugs. In that note, the relevance of this paper and the truncated basic aspects and application on microemulsions are discussed.permeation. Interest in these versatile carriers is increasing and their applications have been diversified to various administration routes in addition to the conventional oral route. This can be attributed to their unique solubilization properties and thermodynamic stability which has drawn attention for their use as novel vehicles for drug delivery [5][6][7].Microemulsions have advantages over both colloidal systems under investigation and conventional emulsions, suspensions and micellar solutions and may provide alternative drug carriers [8]. They are promising delivery systems which allow sustained or controlled drug release for percutaneous, peroral, topical, transdermal, ocular and parenteral administration of medicaments. They offer the advantage of spontaneous formation, ease of manufacturing and scale-up, thermodynamic stability, improved drug solubilization of hydrophobic drugs and bioavailability. Also, microemulsions that have inverse micellar structure may be less comedogenic than either creams or solutions [9,10].Microemulsions are quaternary systems composed of an oil phase, a water system, surfactants and a cosurfactant [11]. These spontaneously formed systems possess specific physicochemical properties such as transparency, optical isotropic, low viscosity and thermodynamic stability. The observed transparency of these systems is due to the fact that the maximum size of the droplets of the dispersed phase is not larger than one-fourth of the wavelength of visible light approximately 150 nm. Droplet diameter in stable microemulsions is usually within the range of 10-100 nm (100-1000 °A), which means that the term 'micro emulsion' is misleading and these systems are actually Nano-sized emulsions. Many studies have shown that micro emulsion formulations possessed improved transdermal and dermal delivery p...