The major objective for studying the impacts of external mechanical forces on agricultural soils is to develop and maintain a well- structured surface that interacts favorably with biological growth; water, heat, and air balances in the soil; and human activities. In this NATO Advanced Research Workshop the discussions were limited to the aspects of soil structure which are influenced by application of external forces, although natural forces such as those created by plant roots, soil fauna, freezing and water content changes are also important. The Workshop offered an opportunity for discussion of information available world-wide and to plan future research, both individually an cooperatively.