When dealing with deep soil improvement, there are two widely known methods, Deep Soil Mixing and Jet Grouting. The Combined Deep Mixing and Jet Grouting method (DMJG) is a relatively new technique integrating the two traditional methods into a single operation to form a solid treated column. This integration has resulted in a larger treatment column diameter, which could not be easily achieved by either of the conventional methods carried out individually. This advantage has led to a faster, cheaper and more efficient means of soil improvement. The construction procedure, treatment parameters and results of a case study in Singapore are presented in this paper.