Generally hypersonic space vehicles are designed with blunt nose to reduce the surface heatflux. However this passive technique enhances the wave drag thus makes the space flight costlier. Hence the space vehicle design has to be carried out by considering the best tradeoff between surface heat load and wave drag. Therefore over the past sixty years development and optimization of hypersonic drag reduction technique is emerged as a major research area in the hypersonic field. Many passive and active techniques have been proposed by different researchers in this field. Efforts are made herewith to summarize the investigations of various researchers about such drag reduction studies. A brief review of the literature reported techniques based on aero-spike, counter-flow injection, energy deposition and surface coating is presented in this article. � Research India Publications.