As a powerful new tool for precision surface cleaning, CO2 snow cleaning involves the formation and acceleration of small dry ice crystals onto a surface. The resulting physical and chemical interactions lead to particle and organic contamination removal. CO2 snow cleaning has proved to be an effective surface cleaning process in many areas. Furthermore, it is a residue free and nondestructive cleaning method. Particle removal has been observed for sizes ranging from visible to less than 40 nanometers; organic contamination removal matches that of commercial solvents to reagent grade solvents. In this article, CO2 snow cleaning is reviewed with emphasis on thermodynamics, cleaning mechanisms, cleaning parameters, equipment, and applications.