Soils deliver a range of soil functions; primary productivity, nutrient cycling, a habitat for biodiversity, water regulation and purification and the breakdown of soil organic matter, which can contribute to climate regulation. Soil biota play an important role in regulating and controlling many of the processes which support these five soil functions. Therefore we need to know which biological methods to apply, to be able to understand the role of soil biodiversity in soil functions. It is also important to know how these biological measures relate to the varying chemical and physical conditions found in soils and the effect of management and climate.