ISO 14688-2:2004, together with ISO 14688-1, establishes the basic principles for the identification and classification of soils on the basis of those material and mass characteristics most commonly used for soils for engineering purposes. The relevant characteristics may vary and therefore, for particular projects or materials, more detailed subdivisions of the descriptive and classification terms may be appropriate.

The classification principles established in ISO 14688-2:2004 permits soils to be grouped into classes of similar composition and geotechnical properties, and with respect to their suitability for geotechnical engineering purposes.

ISO 14688-2:2004 is applicable to natural soil and similar man-made material in situ and redeposited, but it is not a classification of soil by itself.