Soil organisms are the key players in many ecological processes that support healthy soils. In agricultural systems, beneficial soil organisms support achieving high crop yields by suppressing soil-borne diseases, mineralizing organic substrates, and promoting a beneficial soil structure that balances the supply of air and water to plants. In natural systems, the beneficial soil organisms also play a pivotal role in nutrient transformations and plant-soil interactions, shaping the diversity of above-ground plant communities and supporting complex below-ground soil food webs, including higher trophic levels. We welcome empirical studies that relate soil organisms to such ecological processes or soil functions in both natural and agricultural studies. We equally value correlation-based research in large-scale field studies and mechanistic studies that link specific biotic groups to soil processes and functions.