Approximately half of the new drug applicants that reach formulation have poor water solubility. Oral delivery has been the main route of drug administration for the chronic treatment of numerous diseases. In different cases, in oral conveyance, 50 % of the medication compound is hampered because of the high lipid soluble or fat soluble of the medication itself. Around 40 % of new drug applicants show low solubility in water, which prompts poor oral bioavailability, high Intra and Intersubject changeability, and deficiency of dose proportionality Aim of review. The main aim of this review article is to gather the information related to design and evaluation of SMEDDS. These information can be utilized to enhance the bioavailability of the poorly aqueous soluble drug for various types of orally administered drugs. In this review article, various literature are reviewed and summerised in single paper to serve as reference guide to various research scholars and researchers working on self-micro-emulsifying drug delivery systems. Materials and Methods. To prepare this manuscript various keywords were searched in different search engine such as Google, Yahoo and Bing etc. This review article reviews the recent work done in the field of SMEDDS. It comprises review of literatures available in public domain and formulation of SMEDDS and its characterization is summarized in this article. Result. The various strategies to developed poor aqueous soluble drug for improvement of bioavailability for example, salt development and molecular size reduction of the compound might be one technique to enhance the dissolution rate of the drug. In any case, these methods have their limitations. SMEDDS is one of the novel applications for the delivery of low water soluble and low bioavailability of drug. SMEDDS is a method to improve the aqueous solubility of the medication; SMEDDS are described as isotropic blenders of oils, surfactants, and co-surfactant. Upon slightly stir followed by dilution with distilled water, for example, gastrointestinal liquids, these techniques can define clear o/w micro emulsion. SMEDDS is first choice and key technology for developing the lipophilic drug and other different factors that chance to affect the oral bioavailability. Conclusions. This review paper attempts to describe the preparation of SMEDDS and furthermore discusses the development of pseudo ternary phase diagram for SMEDDS. It describes the mechanism and method of preparation involved in SMEDDS. The capability of oral absorption of drug compound from the SMEDDS relies upon numerous formulation−related parameters, for example, surfactant concentration, oil/surfactant ratio, and hydrophobicity of emulsion, globule size and charge, in vitro, in vivo all of which basically characterized the ability of self-emulsification. SMEDDS are administered as unit dosage form and it also protect the degradation of drug.