The purpose of this paper is to describe soil washing and to present results obtained from pilot-scale and full-scale projects. The soil washing system to be described is a water-based physical separation process which relies on traditional physical and chemical extraction and separation processes for removing a broad range of organic, inorganic, and radioactive contaminants from soil. Although soil washing is becoming more accepted as a treatment technology in the United States, limited experience in field application still appears to be a barrier to more widespread implementation. This paper will attempt to overcome some of those barriers by describing the system and its applications, and providing case histories of successful experiences in full-scale and pilot-scale field operations. Both levels of operations have been very successful, and confirm the viability of soil washing for treating contaminated soils.