The present General Report highlights the significant contributions of the papers of Session 4 of the IS-GI Brussels 2012 dedicated to Deep Mixing. As not all papers are reviewed in detail, references are given in order to provide a balanced overview of the entire Technical Session. This General Report discusses the latest developments and current researches in the deep soil mix (DSM) technique. Different execution processes are summarized or classified and their mechanisms are outlined. The DSM material is discussed in detail and various applications of the process are illustrated with the help of case histories. Indeed, during several decades, the DSM technique has been used for ground improvement (GI) applications, but in recent years, DSM was also dedicated to various structural and environmental functions: earth/water retaining structures, foundations, soil reinforcement, land levees and slope stabilization, in situ remediation and barriers against liquefaction. In the present report, the temporary and permanent characters of the DSM structures are also mentioned with regard to the durability aspects of the soil mix material. Current Quality Assurance/Quality Control activities for DSM projects are highlighted. Design of in-situ soil mixing in geotechnical practice is reappraised considering the nature of the DSM material. Many references on the topics discussed are also given in the report.