The increasing value of land and the limited availability of suitable sites for construction are greatly encouraging engineers to consider in situ improvement of weak soil deposits. To economically develop marginal sites a number of ground improvement techniques have been developed as stone columns, jet grouting, compaction grouting, short pile, dynamic compaction, lime stabilization etc. Stone column treatment is one of the most promising and favourable ground improvement techniques widely practiced all over the world. This paper presents a critical review of analytical, experimental, numerical and field studies on the aspect of ordinary and encased stone columns which have been published in the past three decades. Focus is on the recent advancement of encasing these columns with geosynthetic products to enhance their performance in load bearing capacity, decreasing the compressibility, accelerating and reducing the consolidation settlement. Another advantage of encasement is to prevent excessive bulging, squeezing of stone into soft soil. This paper presents installation methods, failure modes of stone columns and brief review of previous researches.